Add environment variable for bot server URL in release workflow

Author: tsjnsn

.github/workflows/release.yml

@@ -8,6 +8,9 @@ on:
 permissions:
   contents: write
 
+env:
+  VITE_BOT_SERVER_URL: ${{ vars.VITE_BOT_SERVER_URL }}
+
 jobs:
   create-release:
     runs-on: ubuntu-latest