[4.x] Flush entire static_cache cache store when running static:clear

[duncanmcclean]

This pull request changes how we clear Static Caching related items from the Laravel cache.

Previously, when the static cache was cleared (either via php please static:clear or other means), we looped through the nocache::urls and cleared the regions from the cache.

This makes sense if we're using the "default" cache store. However, #9405 introduces a new, dedicated static_cache cache store for all things static caching related.

So, instead of us just clearing the keys we can find, this pull request changes our approach to flush the entire static_cache cache store.

If the application doesn't have a static_cache cache store, then it'll fallback to the previous implementation.

Fixes #9765.

[jasonvarga]

I think the underlying issue is more that we aren't keeping track of all keys properly. Or it has something to do with configs changing without clearing caches. Anyway, this PR is a simple quick win. 👍 Thanks!