fix(CI): remove leading slash from git ref

Author: kkweon

.github/workflows/go.yml

@@ -29,7 +29,7 @@ jobs:
       - run: go test -v ./...
 
       - name: Semantic Release
-        if: ${{ github.ref == '/refs/heads/master' }}
+        if: ${{ github.ref == 'refs/heads/master' }}
         id: semantic
         uses: cycjimmy/semantic-release-action@v2
         with:
@@ -40,7 +40,7 @@ jobs:
   docker_release:
     runs-on: ubuntu-latest
 
-    if: ${{ github.ref == '/refs/heads/master' }}
+    if: ${{ github.ref == 'refs/heads/master' }}
 
     needs:
       - build_and_release