[CI] Do not install lix on non lix workflow

Author: kLabz

.github/workflows/main-vanilla.yml

@@ -26,7 +26,7 @@ jobs:
 
     - name: Install npm dependencies
       run: |
-        npm ci
+        npm i terser
 
     - name: Install haxelib dependencies
       if: steps.cache-haxelib.outputs.cache-hit != 'true'