[TASK] Introduce resource Content-Security-Policy check

Introduces Content-Security-Policy HTTP header check on
fileadmin/ resources.

This can be seen as follow-up up to TYPO3-CORE-SA-2020-006
and TYPO3-PSA-2019-010 now actively analyzing this HTTP
header and letting users know in reports module and
system environment check of the Install Tool.

Resolves: #92835
Releases: master, 10.4, 9.5
Change-Id: I53028ae36c9195082993ee89d630efa7b555c547
Reviewed-on: https://review.typo3.org/c/Packages/TYPO3.CMS/+/66627


Tested-by: TYPO3com <noreply@typo3.com>
Tested-by: Markus Klein <markus.klein@typo3.org>
Tested-by: Oliver Hader <oliver.hader@typo3.org>
Reviewed-by: Markus Klein <markus.klein@typo3.org>
Reviewed-by: Oliver Hader <oliver.hader@typo3.org>