Return AndroidPdfViewer based on PDFium

[esensar]

This PR returns previously used AndroidPdfViewer based on updated PDFium which should no longer have security vulnerabilities previously reported (#708). Currently there doesn't seem to be any need for further updates in the app or library code other than what was already done in tibbi/PdfiumAndroid#1.

TODO

• Wait for Update pdfium library tibbi/PdfiumAndroid#1 and update https://github.com/tibbi/AndroidPdfViewer with new ref
• Wait for Update referenced PdfiumAndroid version tibbi/AndroidPdfViewer#1 to update ref in dependencies
• Restore license for AndroidPdfViewer into https://github.com/SimpleMobileTools/Simple-Commons (Bring back license for AndroidPdfViewer Simple-Commons#1722)
• Ensure vulnerability scanner will not complain about this updated version (should not happen, since it is manually checked and pdfium is really updated)

[tibbi]

thanks, should be good