fix push step of bumpup job

.github/workflows/build.yml

@@ -60,7 +60,7 @@ jobs:
           git config user.email "<>"
 
       - name: make changes and push
-      - run: |
+        run: |
          echo '${{ github.ref_name }}' > tag
          git commit -a -m '[Automatic] bumpup version to ${{ github.ref_name }}'
          git push origin master