/home/runner/work/actions-cert-prep/actions-cert-prep/./hello-world-action/action.yml: Expected document start parse event

System.ArgumentException: Unexpected type '' encountered while reading 'action manifest root'. The type 'MappingToken' was expected. at GitHub.DistributedTask.ObjectTemplating.Tokens.TemplateTokenExtensions.AssertMapping(TemplateToken value, String objectDescription) at GitHub.Runner.Worker.ActionManifestManager.Load(IExecutionContext executionContext, String manifestFile)

Failed to load /home/runner/work/actions-cert-prep/actions-cert-prep/./hello-world-action/action.yml

The following actions uses node12 which is deprecated and will be forced to run on node16: actions/checkout@v2. For more info: https://github.blog/changelog/2023-06-13-github-actions-all-actions-will-run-on-node16-instead-of-node12-by-default/