[BUGFIX] Avoid undefined array keys error using stdWrap_bytes

If either labels or base are not given, the default values
kick in: labels = iec and base = 1024

With the new fallback values in place test ContentObjectRendererTest
notAllStdWrapProcessorsAreCallableWithEmptyConfiguration()
needs a minor adaption.

Resolves: #98154
Releases: main, 11.5
Change-Id: Ib2a242454197be94a75fb3d5bffbb8d0be8a1523
Reviewed-on: https://review.typo3.org/c/Packages/TYPO3.CMS/+/75484


Tested-by: Andreas Fernandez <a.fernandez@scripting-base.de>
Tested-by: core-ci <typo3@b13.com>
Tested-by: Christian Kuhn <lolli@schwarzbu.ch>
Reviewed-by: Andreas Fernandez <a.fernandez@scripting-base.de>
Reviewed-by: Christian Kuhn <lolli@schwarzbu.ch>