ci: use swift:6.2-jammy image and fix tar archive paths

- Update CI container to swift:6.2-jammy for consistency with release
- Fix tar command to create archive without ./ prefix in paths

Author: alexey1312

.github/workflows/ci.yml

@@ -71,7 +71,7 @@ jobs:
     runs-on: ubuntu-latest
     needs: lint
     container:
-      image: swift:6.2
+      image: swift:6.2-jammy
     steps:
       - name: Install Git LFS
         run: |

.github/workflows/release.yml

@@ -105,7 +105,7 @@ jobs:
           cp -r .build/${{ matrix.build-path }}/exfig_FlutterExport.resources dist/
           cp -r .build/${{ matrix.build-path }}/exfig_WebExport.resources dist/
           cp LICENSE dist/
-          tar -czf ${{ matrix.archive-name }}.tar.gz -C dist .
+          cd dist && tar -czf ../${{ matrix.archive-name }}.tar.gz *
 
       - name: Upload artifact
         uses: actions/upload-artifact@v4