Protected docx, xlsx, pptx could have stopped to be classified properly

[lfcnassif]

While working on #1793, I tried to put some rules into CustomSignatures.xml to identify iWork 13 files based on extension. As pages, numbers & key extensions are already present in Tika default definitions, I added them as uppercase to avoid extension conflicts. That is a workaround I used before in the past for protected OOXML files:
https://github.com/sepinf-inc/IPED/blob/master/iped-app/resources/config/conf/CustomSignatures.xml#L876-L892

Unfortunately that had no effect and I had to put custom rules into RefineCategoryTask.js. It used to work before and could have stopped to work after the last Tika upgrade. So we should check if protected OOXML MS Office files are still classified properly...

[lfcnassif]

Hopefully this is not happening because we have a hard coded handling of encrypted MS Office documents into SignatureTask. But I found a minor issue while testing this and will open another ticket to fix it. Closing this as invalid.