build(deps): bump ASzc/change-string-case-action from 5 to 6

Bumps [ASzc/change-string-case-action](https://github.com/aszc/change-string-case-action) from 5 to 6.
- [Release notes](https://github.com/aszc/change-string-case-action/releases)
- [Commits](ASzc/change-string-case-action@v5...v6)

---
updated-dependencies:
- dependency-name: ASzc/change-string-case-action
  dependency-type: direct:production
  update-type: version-update:semver-major
...

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

.github/workflows/build.yml

@@ -131,7 +131,7 @@ jobs:
       # https://github.com/macbre/push-to-ghcr/issues/12
       - name: Lowercase Registry
         id: registry_case
-        uses: ASzc/change-string-case-action@v5
+        uses: ASzc/change-string-case-action@v6
         with:
           string: ${{ env.IMAGE_REGISTRY }}