Bump pypdf2 from 1.26.0 to 1.27.9

Bumps [pypdf2](https://github.com/py-pdf/PyPDF2) from 1.26.0 to 1.27.9.
- [Release notes](https://github.com/py-pdf/PyPDF2/releases)
- [Changelog](https://github.com/py-pdf/pypdf/blob/1.27.9/CHANGELOG)
- [Commits](https://github.com/py-pdf/PyPDF2/compare/1.26.0...1.27.9)

---
updated-dependencies:
- dependency-name: pypdf2
  dependency-type: direct:production
...

Signed-off-by: dependabot[bot] <support@github.com>

requirements.txt

@@ -3,4 +3,4 @@ wxPython==4.0.7
 requests==2.24.0
 openpyxl==3.0.5
 Unidecode==1.1.2
-PyPDF2==1.26.0
+PyPDF2==1.27.9