XLIFF 2.1 Export creates invalid XML

Since version 3.2.2 produces the XLIFF 2.1 export invalid XML. 

Reason: one of the explaining comments in the XLF file contains multiple "-" dash signs in a row. This makes the XML invalid.

xmllint sais:

{{xmllint export-2019-07-09-08-26-43.xliff }}

export-2019-07-09-08-26-43.xliff:37: parser error : Double hyphen within comment: <!--

translate5 autostates show the segment state more

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^

export-2019-07-09-08-26-43.xliff:37: parser error : Double hyphen within comment: <!--

translate5 autostates show the segment state more

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