[TASK] Improve strictness of resource access blocking in _.htaccess

[TASK] Improve strictness of resource access blocking in _.htaccess

For Apache HTTP versions 2.3+ there is a better way to avoid conflicts
in priority of sections. Since the `if` condition has been introduced
it is ranked the highest priority, hence it is most suitable for
rules to protect sensitive data.

Resolves: #81849
Releases: master, 8.7
Change-Id: I3f6edf1e3af55dc3ce901080045c8d353eb89ef9
Reviewed-on: https://review.typo3.org/55942
Tested-by: TYPO3com <no-reply@typo3.com>
Reviewed-by: Christian Kuhn <lolli@schwarzbu.ch>
Tested-by: Christian Kuhn <lolli@schwarzbu.ch>