[DOCS] Mark codesnippets in Language API

Resolves: #99083
Releases: main
Change-Id: I8e84db2ca9afdb2dc335fc3b89902f015aec2f87
Reviewed-on: https://review.typo3.org/c/Packages/TYPO3.CMS/+/76596


Tested-by: Stefan Bürk <stefan@buerk.tech>
Reviewed-by: Stefan Bürk <stefan@buerk.tech>
Tested-by: Christian Kuhn <lolli@schwarzbu.ch>
Reviewed-by: Christian Kuhn <lolli@schwarzbu.ch>
Tested-by: core-ci <typo3@b13.com>
Tested-by: Lina Wolf <112@linawolf.de>
Reviewed-by: Lina Wolf <112@linawolf.de>