Update the flags of regolith clean

[Nusiq]

The regolith clean flags are currently very confusing. There are two flags for cleaning files in the user cache folder:

• --user-cache
• --filter-cache
  But there are 3 types of cached files in the user config:
• filters-cache - stores the filters repositories
• project-cache - stores the cache files of the projects (if the user decides to put "use_project_app_data_storage": true in their user configuration.
• resolver-cache - stores the repositories with resolvers.

The names of the flags mismatch the names of the folders and we're missing one flag.

• --user-cache cleans project-cache
• --filter-cache cleans filters-cache (this is almost correct but the user of plural form is inconsistent)
• Nothing cleans the resolver-cache.

We should change the flags to something that makes more sense.

[stirante]

As for the resolver cache, there is an option when installing filters to force fetch resolver --force-resolver-refresh