Test function jit in coverage

Should mostly make ext/opcache/jit/zend_jit.c green.

Author: iluuu1994

.github/workflows/test-suite.yml

@@ -407,12 +407,16 @@ jobs:
         uses: ./.github/actions/install-linux
       - name: Setup
         uses: ./.github/actions/setup-x64
-      # We only test with OpCache, the difference in coverage is negligible
-      - name: Test OpCache
+      - name: Test Tracing JIT
         uses: ./.github/actions/test-linux
         with:
           enableOpcache: true
           jitType: tracing
+      - name: Test Function JIT
+        uses: ./.github/actions/test-linux
+        with:
+          enableOpcache: true
+          jitType: function
       - name: Generate coverage report
         if: ${{ !cancelled() }}
         run: make gcovr-xml