/home/runner/work/lingua-franca/lingua-franca/./lf/.github/actions/prepare-build-env/action.yml: (Line: 14, Col: 4, Idx: 349) - (Line: 14, Col: 4, Idx: 349): While parsing a block mapping, did not find expected key.

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)