Modify bump-version workflow for versioning

Update version retrieval method and remove fetch-tags.

.github/workflows/bump-version.yml

@@ -17,11 +17,10 @@ jobs:
         uses: actions/checkout@v3
         with:
           ref: master
-          fetch-tags: true
 
       - name: Update version in config
         run: |
-          version="$(git describe --tags --abbrev=0)"
+          version="${{ github.ref_name }}"
           sed -i "s/GRUB_BTRFS_VERSION=.*/GRUB_BTRFS_VERSION=${version}/" config
 
       - name: Commit updated config