Resolve "PDF manuscript flow fixes"
Closes #880 (closed)
Similar errors were encountered on further testing PDF manuscript flow
- updating the manuscript throws a cheerio string error for PDF manuscripts, our interim solution for converting base64 to file storage images is skipped as a fix for pdf manuscripts.
- Migration to convert base64 images in the manuscript will fail with cheerio string error as no source HTML will be found in PDF manuscripts. This conversion has been skipped for pdf manuscripts as a fix.