fix: add cache-key config for reusable workflows

[duythien0912]

Description
Using default cache-key will create a lot of caches (out of limit 10GB)

Steps To Reproduce

1. Update 'pubspec.lock'
2. Wait workflow finish
3. See new cache image

Expected Behavior
Have a config for cache-key

Screenshots
Not have

Additional Context
No

[tomarra]

Hi @duythien0912 👋 Thanks for opening this issue.

Given that there has been no activity on this I'm actually going to close this as a won't fix. If this is still something that your facing we will need to get more details in order to triage this fully. If you have that information feel free to reopen the issue with it as a comment.