dependabot-azure-devops: Azure pipeline execution - process '/usr/bin/docker' failed with exit code 1

Error:

...
5c14dd7cf847: Pull complete
72c9e99967c5: Pull complete
Digest: sha256:629e24b3595b970299422de925ea1632535c166a788a1689623667c49c25f065
Status: Downloaded newer image for tingle/dependabot-azure-devops:0.5
warning: parser/current is loading parser/ruby27, which recognizes
warning: 2.7.4-compliant syntax, but you are running 2.7.1.
warning: please see https://github.com/whitequark/parser#compatibility-with-ruby-mri.
/home/dependabot/dependabot-script/vendor/ruby/2.7.0/gems/dependabot-nuget-0.159.0/lib/dependabot/nuget/file_fetcher.rb:42:in `fetch_files': Dependabot::DependencyFileNotFound (Dependabot::DependencyFileNotFound)
	from /home/dependabot/dependabot-script/vendor/ruby/2.7.0/gems/dependabot-common-0.159.0/lib/dependabot/file_fetchers/base.rb:65:in `files'
	from ./update-script.rb:245:in `<main>'
Using hostname = 'dev.azure.com', protocol = 'https', port = '443'.
Using 'https://dev.azure.com:443/' as API endpoint
Fetching nuget dependency files for XXX/Dev/_git/XXX-example
Targeting 'master' branch under '/src' directory
Using 'auto' requirements update strategy
##[error]The process '/usr/bin/docker' failed with exit code 1
...

Pipeline:

pool:
  vmImage: 'ubuntu-latest'

steps:
  - task: dependabot@1
    inputs:
      packageManager: 'nuget'
      directory: '/src'
      targetBranch: 'master'
      versioningStrategy: 'auto'
      setAutoComplete: true
      azureDevOpsAccessToken: '$(PAT)'
      targetRepositoryName: 'XXX-example'

I can’t see any different error than process '/usr/bin/docker' failed with exit code 1. Can you help me with that?