Bump rdflib from 7.1.3 to 7.2.1

Bumps [rdflib](https://github.com/RDFLib/rdflib) from 7.1.3 to 7.2.1.
- [Release notes](https://github.com/RDFLib/rdflib/releases)
- [Changelog](https://github.com/RDFLib/rdflib/blob/main/CHANGELOG.md)
- [Commits](RDFLib/rdflib@7.1.3...7.2.1)

---
updated-dependencies:
- dependency-name: rdflib
  dependency-version: 7.2.1
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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

Author: dependabot[bot]

requirements.txt

@@ -3,7 +3,7 @@ Flask==3.1.0
 Flask-Cors==6.0.1
 pyaml==25.5.0
 python-gitlab==6.2.0
-rdflib==7.1.3
+rdflib==7.2.1
 requests==2.32.3
 SPARQLTransformer==2.4.0
 PyGithub==2.6.1