fastlane: Server error got 500, but IPA file still success in TestFlight

New Issue Checklist

• Updated fastlane to the latest version
• I read the Contribution Guidelines
• I read docs.fastlane.tools
• I searched for existing GitHub issues

Issue Description

I run my lane (fastlane beta) which builds and pushes up to TestFlight. Used to work fine, now ends with:

[11:23:22]: fastlane finished with errors
Looking for related GitHub issues on fastlane/fastlane...
...
(Shows some issues which are closed and appear different/unrelated)
...
[!] The request could not be completed because:
	Server error got 500

Interestingly, the app is still pushed successfully to TestFlight and can be run as usual. I can essentially ignore this error and go about business as usual.

My Fastfile

default_platform(:ios)

platform :ios do

  desc "Increment Build Number"
  lane :increment do
    increment_build_number(xcodeproj: "CmsMmobileAapp.xcodeproj")
  end

  desc "Remove NSExceptionDomains"
  lane :NSExceptionDomains do
  update_info_plist(
    plist_path: "CmsMmobileAapp/Info.plist",
    block: proc do |plist|
      plist[:NSAppTransportSecurity] = {}
    end
  )
  end

  desc "Push a new beta build to TestFlight"
  lane :beta do
    NSExceptionDomains()
    build_app(scheme: "CmsMmobileAapp", configuration: "Release")
    upload_to_testflight
  end

end

Complete output when running fastlane, including the stack trace and command used

With --capture_output it ends with this:

INFO [2018-09-27 11:49:37.13]: Successfully finished processing the build 1.2 - 46
INFO [2018-09-27 11:49:37.13]: Distributing new build to testers: 1.2 - 46
WARN [2018-09-27 11:49:37.63]: Lane Context:
INFO [2018-09-27 11:49:37.63]: {:DEFAULT_PLATFORM=>:ios, :PLATFORM_NAME=>:ios, :LANE_NAME=>"ios beta", :IPA_OUTPUT_PATH=>"/Users/lancedolan/sourcecode/CmsMmobileAapp/ios/CmsMmobileAapp.ipa", :DSYM_OUTPUT_PATH=>"/Users/lancedolan/sourcecode/CmsMmobileAapp/ios/CmsMmobileAapp.app.dSYM.zip", :XCODEBUILD_ARCHIVE=>"/Users/lancedolan/Library/Developer/Xcode/Archives/2018-09-27/CmsMmobileAapp 2018-09-27 11.43.36.xcarchive"}
ERROR [2018-09-27 11:49:37.63]: Server error got 500
INFO [2018-09-27 11:49:37.63]: Successfully generated documentation at path '/Users/lancedolan/sourcecode/CmsMmobileAapp/ios/fastlane/README.md'
ERROR [2018-09-27 11:49:37.64]: fastlane finished with errors

Environment

# This file contains the fastlane.tools configuration
# You can find the documentation at https://docs.fastlane.tools
#
# For a list of all available actions, check out
#
#     https://docs.fastlane.tools/actions
#
# For a list of all available plugins, check out
#
#     https://docs.fastlane.tools/plugins/available-plugins
#

# Uncomment the line if you want fastlane to automatically update itself
# update_fastlane

default_platform(:ios)

platform :ios do

  desc "Increment Build Number"
  lane :increment do
    increment_build_number(xcodeproj: "CmsMmobileAapp.xcodeproj")
  end

  desc "Remove NSExceptionDomains"
  lane :NSExceptionDomains do
  update_info_plist(
    plist_path: "CmsMmobileAapp/Info.plist",
    block: proc do |plist|
      plist[:NSAppTransportSecurity] = {}
    end
  )
  end

  desc "Push a new beta build to TestFlight"
  lane :beta do
    NSExceptionDomains()
    build_app(scheme: "CmsMmobileAapp", configuration: "Release")
    upload_to_testflight
  end

end

app_identifier("CHANGED.CHANGED.CHANGED") # The bundle identifier of your app
apple_id("CHANGED@CHANGED.com") # Your Apple email address

itc_team_id("CHANGED") # iTunes Connect Team ID
team_id("CHANGED") # Developer Portal Team ID

# For more information about the Appfile, see:
#     https://docs.fastlane.tools/advanced/#appfile