Indexing Templavoila Contentelement doesn't work for translations

The Elements were rendered through a initialized TSFE. The TSFE is initialized with default language.  
The language option in code is currently not present. See [getTemplavoilaElementContent](https://github.com/DMKEBUSINESSGMBH/typo3-mksearch/blob/ba11afd78779595b86f015a47025e158f6818361/indexer/ttcontent/class.tx_mksearch_indexer_ttcontent_Templavoila.php#L218).