Fix CI workflow parse error

    Error: /home/runner/work/rust-toolchain/rust-toolchain/./action.yml (Line: 27, Col: 18): A template expression is not allowed in this context
    Error: /home/runner/work/rust-toolchain/rust-toolchain/./action.yml (Line: 27, Col: 18): A template expression is not allowed in this context
    Error: GitHub.DistributedTask.ObjectTemplating.TemplateValidationException: The template is not valid. /home/runner/work/rust-toolchain/rust-toolchain/./action.yml (Line: 27, Col: 18): A template expression is not allowed in this context
       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)
    Error: Fail to load /home/runner/work/rust-toolchain/rust-toolchain/./action.yml

Author: dtolnay

action.yml

@@ -24,7 +24,7 @@ outputs:
     description: A short hash of the rustc version, appropriate for use as a cache key. "20220627a831"
     value: ${{steps.rustc-version.outputs.cachekey}}
   name:
-    description: Rustup's name for this version of the toolchain, suitable for use with `${{'cargo +${{steps.toolchain.outputs.name}}'}}`.
+    description: Rustup's name for the selected version of the toolchain. "1.62.0"  # suitable for use with `cargo +${{steps.toolchain.outputs.name}}`
     value: ${{steps.parse.outputs.toolchain}}
 
 runs: