[BETA][FEATURE] Add TYPO3 v13 compatibility

[twoldanski]

Headlines: TYPO3 v13 compatibility

• add TYPO3 v13.3 support with support v12 at the same time
• align code style with latest typo3/coding-standards
• bump typo3/testingframework

[coveralls]

Pull Request Test Coverage Report for Build 11513582467

Details

• 1 of 1 (100.0%) changed or added relevant line in 1 file are covered.
• 2 unchanged lines in 1 file lost coverage.
• Overall coverage increased (+4.8%) to 72.782%

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Files with Coverage Reduction	New Missed Lines	%
Classes/Utility/FileUtility.php	2	93.91%
<!--	Total:	2		-->

Totals
Change from base Build 11234707417:	4.8%
Covered Lines:	1083
Relevant Lines:	1488

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💛 - Coveralls