Failed to load dtolnay/rust-toolchain/stable/action.yml

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)

dtolnay/rust-toolchain/stable/action.yml: (Line: 39, Col: 5, Idx: 1208) - (Line: 39, Col: 5, Idx: 1208): While parsing a block collection, did not find expected '-' indicator.