gatsby: gatsby-plugin-feed showing errors and warnings on build

Description

Running gatsby build while using the gatsby-plugin-feed with MDX, I can see quite a few webpack deprecation errors and also some gatsby-plugin-mdx warnings.

Steps to reproduce

• Clone and checkout this branch: https://github.com/pedrolamas/pedrolamas.com/tree/temp
• Run yarn && yarn build and observe the error messages.

Expected result

No build errors/warnings should be shown.

Actual result

$ yarn gatsby build --verbose
yarn run v1.22.10
$ D:\Projects\pedrolamas.com\node_modules\.bin\gatsby build --verbose
verbose set gatsby_log_level: "verbose"
verbose set gatsby_executing_command: "build"
verbose loading local command from: D:\Projects\pedrolamas.com\node_modules\gatsby\dist\commands\build.js
verbose running command: build
success open and validate gatsby-configs - 0.125s
success load plugins - 1.482s
success onPreInit - 0.044s
info One or more of your plugins have changed since the last time you ran Gatsby. As
a precaution, we're deleting your site's cache to ensure there's no stale data.
success initialize cache - 0.084s
success copy gatsby files - 0.100s
success onPreBootstrap - 0.020s
success createSchemaCustomization - 0.005s
verbose Checking for deleted pages
verbose Deleted 0 pages
verbose Found 0 changed pages
success Checking for changed pages - 0.004s
success source and transform nodes - 5.538s
success building schema - 0.640s
info Total nodes: 1273, SitePage nodes: 246 (use --verbose for breakdown)
verbose Number of node types: 10. Nodes per type: SitePage: 246, SitePlugin: 58, Site: 1, SiteBuildMetadata: 1, MdxSource: 2, Mdx: 110, Directory: 72, File: 464, ImageSharp: 312, SitemapYaml: 7
success createPages - 0.175s
verbose Checking for deleted pages
verbose Deleted 0 pages
verbose Found 245 changed pages
success Checking for changed pages - 0.002s
success createPagesStatefully - 0.509s
success Cleaning up stale page-data - 0.010s
success update schema - 0.079s
success onPreExtractQueries - 0.001s
success extract queries from components - 1.264s
success write out redirect data - 0.001s
success Build manifest and related icons - 0.053s
success onPostBootstrap - 0.129s
info bootstrap finished - 13.182s
success run static queries - 0.293s - 2/2 6.83/s
success run page queries - 12.069s - 270/270 22.37/s
success write out requires - 0.009s
success Building production JavaScript and CSS bundles - 15.865s
success Building HTML renderer - 5.940s
success Building static HTML for pages - 1.376s - 270/270 196.20/s

 ERROR

(node:44388) [DEP_WEBPACK_COMPILATION_ADDITIONAL_CHUNK_ASSETS] DeprecationWarning: additionalChunkAssets is deprecated (use Compilation.hooks.processAssets instead and use one of Compilation.PROCESS_ASSETS_STAGE_* as stage option)
(Use `node --trace-deprecation ...` to show where the warning was created)


 ERROR

(node:44388) [DEP_WEBPACK_COMPILATION_OPTIMIZE_CHUNK_ASSETS] DeprecationWarning: optimizeChunkAssets is deprecated (use Compilation.hooks.processAssets instead and use one of Compilation.PROCESS_ASSETS_STAGE_* as stage option)


 ERROR

(node:44388) [DEP_WEBPACK_COMPILATION_AFTER_OPTIMIZE_CHUNK_ASSETS] DeprecationWarning: afterOptimizeChunkAssets is deprecated (use Compilation.hooks.processAssets instead and use one of Compilation.PROCESS_ASSETS_STAGE_* as stage
option)


 ERROR

(node:44388) [DEP_WEBPACK_COMPILATION_NORMAL_MODULE_LOADER_HOOK] DeprecationWarning: Compilation.hooks.normalModuleLoader was moved to NormalModule.getCompilationHooks(compilation).loader


 ERROR

(node:44388) [DEP_WEBPACK_DEPRECATION_ARRAY_TO_SET_LENGTH] DeprecationWarning: chunk.files was changed from Array to Set (using Array property 'length' is deprecated)


 ERROR

(node:44388) [DEP_WEBPACK_CONTEXT_MODULE_FACTORY_ALTERNATIVES] DeprecationWarning: ContextModuleFactory.hooks.alternatives has deprecated in favor of ContextModuleFactory.hooks.alternativeRequests with an additional options argument.

warn gatsby-plugin-mdx
[object Object]
warn gatsby-plugin-mdx
[object Object]
warn gatsby-plugin-mdx
[object Object]
warn gatsby-plugin-mdx
[object Object]
warn gatsby-plugin-mdx
[object Object]
warn gatsby-plugin-mdx
[object Object]
warn gatsby-plugin-mdx
[object Object]
warn gatsby-plugin-mdx
[object Object]
warn gatsby-plugin-mdx
[object Object]
warn gatsby-plugin-mdx
[object Object]
warn gatsby-plugin-mdx
[object Object]
warn gatsby-plugin-mdx
[object Object]
warn gatsby-plugin-mdx
[object Object]
warn gatsby-plugin-mdx
[object Object]
warn gatsby-plugin-mdx
[object Object]
warn gatsby-plugin-mdx
[object Object]
warn gatsby-plugin-mdx
[object Object]
warn gatsby-plugin-mdx
[object Object]
warn gatsby-plugin-mdx
[object Object]
warn gatsby-plugin-mdx
[object Object]
warn gatsby-plugin-mdx
[object Object]
warn gatsby-plugin-mdx
[object Object]
info Generated public/sw.js, which will precache 10 files, totaling 564195 bytes.
The following pages will be precached:
/offline-plugin-app-shell-fallback/index.html
success onPostBuild - 9.115s
info Done building in 58.1989875 sec

Done in 58.47s.

Environment

System: OS: Windows 10 10.0.19043 CPU: (12) x64 Intel® Core™ i7-10750H CPU @ 2.60GHz Binaries: Node: 14.15.1 - ~\AppData\Local\Temp\yarn–1618927948804-0.9999846084110822\node.CMD Yarn: 1.22.10 - ~\AppData\Local\Temp\yarn–1618927948804-0.9999846084110822\yarn.CMD npm: 7.5.2 - C:\Program Files\nodejs\npm.CMD Languages: Python: 2.7.15 Browsers: Edge: Spartan (44.19041.906.0), Chromium (89.0.774.77), ChromiumDev (91.0.852.0) npmPackages: gatsby: ^3.3.0 => 3.3.1 gatsby-plugin-env-variables: ^2.1.0 => 2.1.0 gatsby-plugin-eslint: ^3.0.0 => 3.0.0 gatsby-plugin-feed: ^3.3.0 => 3.3.0 gatsby-plugin-google-analytics: ^3.3.0 => 3.3.0 gatsby-plugin-image: ^1.3.0 => 1.3.1 gatsby-plugin-manifest: ^3.3.0 => 3.3.0 gatsby-plugin-mdx: ^2.3.0 => 2.3.0 gatsby-plugin-netlify: ^3.3.0 => 3.3.0 gatsby-plugin-offline: ^4.3.0 => 4.3.0 gatsby-plugin-react-helmet: ^4.3.0 => 4.3.0 gatsby-plugin-robots-txt: ^1.5.5 => 1.5.6 gatsby-plugin-sass: ^4.3.0 => 4.3.0 gatsby-plugin-sharp: ^3.3.0 => 3.3.1 gatsby-plugin-sitemap: ^3.3.0 => 3.3.0 gatsby-plugin-twitter: ^3.3.0 => 3.3.0 gatsby-remark-acronyms: ^1.1.3 => 1.1.3 gatsby-remark-copy-linked-files: ^4.0.0 => 4.0.0 gatsby-remark-images: ^5.0.0 => 5.0.0 gatsby-remark-responsive-iframe: ^4.0.0 => 4.0.0 gatsby-remark-smartypants: ^4.0.0 => 4.0.0 gatsby-source-filesystem: ^3.3.0 => 3.3.0 gatsby-transformer-sharp: ^3.3.0 => 3.3.0 gatsby-transformer-yaml: ^3.3.0 => 3.3.0