Bump msgraph-core from 1.1.2 to 1.1.8 (#2245)

Bumps [msgraph-core](https://github.com/microsoftgraph/msgraph-sdk-python-core) from 1.1.2 to 1.1.8.
- [Release notes](https://github.com/microsoftgraph/msgraph-sdk-python-core/releases)
- [Changelog](https://github.com/microsoftgraph/msgraph-sdk-python-core/blob/main/CHANGELOG.md)
- [Commits](microsoftgraph/msgraph-sdk-python-core@v1.1.2...v1.1.8)

---
updated-dependencies:
- dependency-name: msgraph-core
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

Signed-off-by: dependabot[bot] <[email protected]>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

Author: dependabot[bot]

app/backend/requirements.txt

@@ -191,7 +191,7 @@ msal==1.30.0
     #   msal-extensions
 msal-extensions==1.2.0
     # via azure-identity
-msgraph-core==1.1.2
+msgraph-core==1.1.8
     # via msgraph-sdk
 msgraph-sdk==1.16.0
     # via -r requirements.in