[🔨chore]: zero install로 인하여 github actions환경에서 의존성 설치시 --immutable명령어 추가

.github/workflows/buildTest.yaml

@@ -11,8 +11,6 @@ jobs:
     steps:
       - name: Checkout
         uses: actions/checkout@v4
-        with:
-          ref: ${{ github.head_ref }}
 
       - name: Set up Node
         uses: actions/setup-node@v4
@@ -26,6 +24,9 @@ jobs:
         run: |
           yarn set version 4.1.0
 
+      - name: Install dependencies
+        run: yarn install --immutable --immutable-cache
+
       - name: Test utility functions
         run: yarn run test