chore(deps): update pypdf requirement from ==5.1.* to ==6.3.*

Updates the requirements on [pypdf](https://github.com/py-pdf/pypdf) to permit the latest version.
- [Release notes](https://github.com/py-pdf/pypdf/releases)
- [Changelog](https://github.com/py-pdf/pypdf/blob/main/CHANGELOG.md)
- [Commits](py-pdf/pypdf@5.1.0...6.3.0)

---
updated-dependencies:
- dependency-name: pypdf
  dependency-version: 6.3.0
  dependency-type: direct:production
...

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

Author: dependabot[bot]

pyproject.toml

@@ -35,7 +35,7 @@ dependencies = [
         'django-cors-headers',
         'reportlab==4.2.*',
         'Pillow==12.0.*',
-        'pypdf==5.1.*',
+        'pypdf==6.3.*',
         'django-libsass==0.9',
         'libsass==0.23.*',
         'django-otp==1.6.*',