Use a more optimized caching strategy for 'coverage-frontend'

Signed-off-by: Rémy Coutable <remy@rymai.me>

.gitlab/ci/frontend.gitlab-ci.yml

@@ -250,11 +250,13 @@ jest-as-if-foss:
 coverage-frontend:
   extends:
     - .default-retry
+    - .yarn-cache
     - .frontend:rules:ee-mr-and-master-only
   needs: ["jest"]
   stage: post-test
   before_script:
-    - yarn install --frozen-lockfile --cache-folder .yarn-cache --prefer-offline
+    - source scripts/utils.sh
+    - retry yarn install --frozen-lockfile
   script:
     - yarn node scripts/frontend/merge_coverage_frontend.js
   artifacts:
@@ -263,8 +265,7 @@ coverage-frontend:
     paths:
       - coverage-frontend/
   cache:
-    paths:
-      - .yarn-cache/
+    policy: pull
 
 .qa-frontend-node:
   extends:

.gitlab/ci/review.gitlab-ci.yml

@@ -238,3 +238,5 @@ danger-review:
     - source scripts/utils.sh
     - retry yarn install --frozen-lockfile
     - danger --fail-on-errors=true --verbose
+  cache:
+    policy: pull