If page.includeCSS.myfile.import = 1 is used, but no "media" is set, a TypeError
is thrown, which is now caught and properly checked.

Resolves: #88059
Releases: master, 9.5
Change-Id: I0951688bb9ee779329ebe5c7fad698862d73f6c3
Reviewed-on: https://review.typo3.org/c/Packages/TYPO3.CMS/+/60420


Tested-by: TYPO3com <noreply@typo3.com>
Tested-by: Julian Geils <j_geils@web.de>
Tested-by: Tobi Kretschmann <tobi@tobishome.de>
Tested-by: Benni Mack <benni@typo3.org>
Reviewed-by: Julian Geils <j_geils@web.de>
Reviewed-by: Tobi Kretschmann <tobi@tobishome.de>
Reviewed-by: Benni Mack <benni@typo3.org>