Replace usages of deprecated ExtbaseEnvironmentService

[tmotyl]

Extbase EnvironmentService was deprecated in v11 and removed in v12.
It's used in several places in the extension and is one of the blockers to make extension compatible with v12

https://docs.typo3.org/c/typo3/cms-core/11.5/en-us/Changelog/11.2/Deprecation-92494-ExtbaseEnvironmentService.html

[sfroemkenjw]

As long as maps2 is still TYPO3 10 compatible I can not remove that service.
I will remove that while upgrading to TYPO3 12. With that upgrade I also remove the TYPO3 10 compatibility

[sfroemkenjw]

Hello @tmotyl

thank you for providing this issue. On my typo3_12_compatibility branch I already have migrated the extbase EnvironmentService to TYPO3_REQUEST->isFrontend()

Have a cool start into this new week

Stefan