Bump cda-tum/mqt-workflows in the github-actions group

Bumps the github-actions group with 1 update: [cda-tum/mqt-workflows](https://github.com/cda-tum/mqt-workflows).


Updates `cda-tum/mqt-workflows` from 1.1.5 to 1.2.1
- [Release notes](https://github.com/cda-tum/mqt-workflows/releases)
- [Commits](cda-tum/mqt-workflows@v1.1.5...v1.2.1)

---
updated-dependencies:
- dependency-name: cda-tum/mqt-workflows
  dependency-type: direct:production
  update-type: version-update:semver-minor
  dependency-group: github-actions
...

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

.github/workflows/update-mqt-core.yml

@@ -21,6 +21,6 @@ concurrency:
 jobs:
   update-mqt-core:
     name: ⬆️ Update MQT Core
-    uses: cda-tum/mqt-workflows/.github/workflows/reusable-mqt-core-update.yml@v1.1.5
+    uses: cda-tum/mqt-workflows/.github/workflows/reusable-mqt-core-update.yml@v1.2.1
     with:
       update-to-head: ${{ fromJSON(github.event.inputs.update-to-head) || false }}