(fix) Move changelog job to it's own workflow (#720)

- moved the job to its own workflow file
- changed the label to `skip changelog`

.github/workflows/ci.yml

@@ -68,18 +68,3 @@ jobs:
     - name: Clippy
       run: cargo clippy
 
-  Changelog:
-    name: Changelog Check
-    runs-on: ubuntu-latest
-    steps:
-    - uses: actions/checkout@v3
-    - name: Changelog check
-    
-      uses: Zomzog/changelog-checker@v1.3.0
-      with:
-        fileName: CHANGELOG.md 
-        noChangelogLabel: no changelog
-        checkNotification: Simple
-      env:
-        GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
-