[TASK] Define cache.assets in service provider

The cache.assets container entry was pregenerated in Bootstrap
for historic reasons: it used to be statically injected into
the IconRegistry and PageRenderer from Bootstrap::init().

This has been refactored with #93475 and #97030, therefore
assets cache generation can now be delayed until it is actually
needed.

Note: It is needed in uncached installtool context, therefore
it is provided in ServiceProvider.php instead of Services.yaml

Resolves: #104305
Related: #93475
Related: #97030
Releases: main
Change-Id: I3a0f1a5b6f01ed19da79d2547b418029d68bf0f1
Reviewed-on: https://review.typo3.org/c/Packages/TYPO3.CMS/+/85102


Tested-by: Georg Ringer <georg.ringer@gmail.com>
Reviewed-by: Benni Mack <benni@typo3.org>
Reviewed-by: Georg Ringer <georg.ringer@gmail.com>
Tested-by: Benni Mack <benni@typo3.org>
Tested-by: core-ci <typo3@b13.com>