Bump azure-monitor-opentelemetry from 1.6.3 to 1.6.8

Bumps [azure-monitor-opentelemetry](https://github.com/Azure/azure-sdk-for-python) from 1.6.3 to 1.6.8.
- [Release notes](https://github.com/Azure/azure-sdk-for-python/releases)
- [Changelog](https://github.com/Azure/azure-sdk-for-python/blob/main/doc/esrp_release.md)
- [Commits](Azure/azure-sdk-for-python@azure-monitor-opentelemetry_1.6.3...azure-monitor-opentelemetry_1.6.8)

---
updated-dependencies:
- dependency-name: azure-monitor-opentelemetry
  dependency-version: 1.6.8
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

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

Author: dependabot[bot]

src/backend/requirements.txt

@@ -34,7 +34,7 @@ azure-core-tracing-opentelemetry==1.0.0b11
     # via azure-monitor-opentelemetry
 azure-identity==1.19.0
     # via fastapi-app (pyproject.toml)
-azure-monitor-opentelemetry==1.6.3
+azure-monitor-opentelemetry==1.6.8
     # via fastapi-app (pyproject.toml)
 azure-monitor-opentelemetry-exporter==1.0.0b32
     # via azure-monitor-opentelemetry