chore(deps): bump pypdf from 5.4.0 to 5.6.0

Bumps [pypdf](https://github.com/py-pdf/pypdf) from 5.4.0 to 5.6.0.
- [Release notes](https://github.com/py-pdf/pypdf/releases)
- [Changelog](https://github.com/py-pdf/pypdf/blob/main/CHANGELOG.md)
- [Commits](py-pdf/pypdf@5.4.0...5.6.0)

---
updated-dependencies:
- dependency-name: pypdf
  dependency-version: 5.6.0
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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

Author: dependabot[bot]

requirements/base.txt

@@ -12,5 +12,5 @@ pinecone-text==0.10.0
 pydantic==2.10.4
 pydantic-settings==2.7.1
 python-dotenv==1.1.0
-pypdf==5.4.0
+pypdf==5.6.0
 tiktoken==0.9.0