Hi there! Thanks for the great extension to the actions/cache action - I'm using it to great effect to provide longer term caches via S3 rather than GitHub's 7-day caching.

I was however a little confused about some of the outputs. For example, actions/cache specifies a cache-matched-key output, which seems to be mapped to matched-key in this action. When I tried to use this output value to confirm if the key matched or any restore-keys prefix matched, the cache-matched-key or matched-key outputs are not available - only cache-hit and cache-size are provided.

Would it be possible to:

• improve the documentation so that the outputs are listed in the README?
• add the cache-matched-key or matched-key to the available outputs?

Thank you!