Update build.yml

Author: xplshn

.github/workflows/build.yml

@@ -63,7 +63,9 @@ jobs:
 
       - name: Create submodules tarball
         run: |
+          apk add tar
           tar -czf submodules.tar.gz .git/modules
+          apk del tar
 
       - uses: actions/upload-artifact@v4
         with: