[BUGFIX] Build extbase attribute in UriBuilder fallback

With getRequest() in UriBuilder returning a
extbase Request in the fallback chain, we need
to have an extbase attribute when creating it.

Also avoid another call to $GLOBALS['TYPO3_REQUEST'].

Resolves: #99770
Related: #99650
Related: #99734
Related: #99757
Releases: main
Change-Id: Ic59394172a0834efbd2caada23cbf776322a8e11
Reviewed-on: https://review.typo3.org/c/Packages/TYPO3.CMS/+/77648


Reviewed-by: Benni Mack <benni@typo3.org>
Tested-by: core-ci <typo3@b13.com>
Tested-by: Torben Hansen <derhansen@gmail.com>
Tested-by: Benni Mack <benni@typo3.org>
Reviewed-by: Torben Hansen <derhansen@gmail.com>