ci: Fix get tag name for snapcraft promote

.github/workflows/release.yaml

@@ -179,6 +179,9 @@ jobs:
         uses: actions/checkout@v4
       - name: Install Snapcraft
         uses: samuelmeuli/action-snapcraft@v2
+      - name: Get Tag Name
+        id: tag_name
+        run: echo "::set-output name=tag::$(echo ${GITHUB_REF#refs/tags/})"
       - name: Promote Snap
         env: # Workaround for https://github.com/snapcore/snapcraft/issues/4439
           SNAPCRAFT_HAS_TTY: "true"
@@ -187,4 +190,4 @@ jobs:
               yes | snapcraft promote fluffychat --from-channel edge --to-channel candidate
           else
               yes | snapcraft promote fluffychat --from-channel edge --to-channel stable
-          fi
+          fi