/home/runner/work/nginx/nginx/./.github/actions/test-kitchen/action.yml (Line: 21, Col: 23): Unrecognized named-value: 'var'. Located at position 1 within expression: var.CHEF_VERSION || 'current'

GitHub.DistributedTask.ObjectTemplating.TemplateValidationException: The template is not valid. /home/runner/work/nginx/nginx/./.github/actions/test-kitchen/action.yml (Line: 21, Col: 23): Unrecognized named-value: 'var'. Located at position 1 within expression: var.CHEF_VERSION || 'current' at GitHub.DistributedTask.ObjectTemplating.TemplateValidationErrors.Check() 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)

Failed to load /home/runner/work/nginx/nginx/./.github/actions/test-kitchen/action.yml