Bump cyclonedx-python-lib from 6.4.4 to 7.6.1 in /backend

Bumps [cyclonedx-python-lib](https://github.com/CycloneDX/cyclonedx-python-lib) from 6.4.4 to 7.6.1.
- [Release notes](https://github.com/CycloneDX/cyclonedx-python-lib/releases)
- [Changelog](https://github.com/CycloneDX/cyclonedx-python-lib/blob/main/CHANGELOG.md)
- [Commits](CycloneDX/cyclonedx-python-lib@v6.4.4...v7.6.1)

---
updated-dependencies:
- dependency-name: cyclonedx-python-lib
  dependency-type: direct:production
  update-type: version-update:semver-major
...

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

backend/requirements.txt

@@ -6,7 +6,7 @@ cachelib==0.13.0
 certifi==2024.2.2
 charset-normalizer==3.3.2
 click==8.1.7
-cyclonedx-python-lib==6.4.4
+cyclonedx-python-lib==7.6.1
 defusedxml==0.7.1
 filelock==3.13.3
 Flask==3.0.0