[action] remove duplicate step in job

.github/workflows/release.yml

@@ -29,15 +29,6 @@ jobs:
         name: Lint, Test, Build
         id: lint_test_build
         run: V=1 make -j1 bootstrap ci
-      -
-        name: Is Pre-release
-        id: is_prerelease
-        run: |
-          set +e
-          echo ${{ github.ref }} | grep "\-rc.*"
-          OUT=$?
-          if [ $OUT -eq 0 ]; then IS_PRERELEASE=true; else IS_PRERELEASE=false; fi
-          echo "::set-output name=IS_PRERELEASE::${IS_PRERELEASE}"
 
   create_release:
     name: Create Release