Remove control characters

[seirerman]

I have some files that have control characters (eg. BEL, VT, NAK, DC3...) in the metadata (see attachment: 70-2021-290-5-23-12-2021.pdf). See also https://en.wikipedia.org/wiki/ASCII#Control_code_chart for a list of control characters.

The extractor extension doesn't remove those special characters when a new file is imported into TYPO3. This leads to solr getting stuck while indexing the affected files, which stops all following files in the queue from indexing.