/home/runner/work/FEDC4_MUSSEUK_LETTER_Donggeun/FEDC4_MUSSEUK_LETTER_Donggeun/./.github/actions/setup/action.yml (Line: 3, Col: 3): A sequence was not expected

System.ArgumentException: Unexpected type 'SequenceToken' encountered while reading 'runs'. The type 'MappingToken' was expected. at GitHub.DistributedTask.ObjectTemplating.Tokens.TemplateTokenExtensions.AssertMapping(TemplateToken value, String objectDescription) at GitHub.Runner.Worker.ActionManifestManager.ConvertRuns(IExecutionContext executionContext, TemplateContext templateContext, TemplateToken inputsToken, String fileRelativePath, MappingToken outputs) at GitHub.Runner.Worker.ActionManifestManager.Load(IExecutionContext executionContext, String manifestFile)