[BUGIFX] Improve labels in clear cache menu items

With the changes introduced by the new cache grouping system, the
"Clear all cache" menu item in the clear cache menu has become
ambiguous. Labels and tooltips can be improved.

Resolves: #57128
Releases: 6.2
Change-Id: I2c723e3581605f7040f8a1cc1598053155ee80a4
Reviewed-on: https://review.typo3.org/28588
Reviewed-by: Xavier Perseguers
Tested-by: Xavier Perseguers
Reviewed-by: Ludwig Rafelsberger
Reviewed-by: Stephan Großberndt
Reviewed-by: Jigal van Hemert
Tested-by: Jigal van Hemert