Bump pypdf from 5.6.0 to 6.1.3 in /infra/scripts/index_scripts

Bumps [pypdf](https://github.com/py-pdf/pypdf) from 5.6.0 to 6.1.3.
- [Release notes](https://github.com/py-pdf/pypdf/releases)
- [Changelog](https://github.com/py-pdf/pypdf/blob/main/CHANGELOG.md)
- [Commits](py-pdf/pypdf@5.6.0...6.1.3)

---
updated-dependencies:
- dependency-name: pypdf
  dependency-version: 6.1.3
  dependency-type: direct:production
...

Signed-off-by: dependabot[bot] <[email protected]>

Author: dependabot[bot]

infra/scripts/index_scripts/requirements.txt

@@ -1,6 +1,6 @@
 azure-storage-file-datalake==12.20.0
 openai==1.84.0
-pypdf==5.6.0
+pypdf==6.1.3
 # pyodbc
 tiktoken==0.9.0
 msal[broker]==1.32.3