CI: cache installed dependencies

.github/workflows/test.yml

@@ -1,23 +1,16 @@
 name: Test
-
 on: [push, pull_request]
-
 jobs:
   test:
     strategy:
       fail-fast: false
       matrix:
         ruby: ["2.5", "2.6", "2.7", "3.0", "3.1", "3.2", "3.3"]
     runs-on: ubuntu-latest
-
     steps:
-      - name: Checkout
-        uses: actions/checkout@v2
-      - name: Set up Ruby
-        uses: ruby/setup-ruby@v1
+      - uses: actions/checkout@v4
+      - uses: ruby/setup-ruby@v1
         with:
           ruby-version: ${{ matrix.ruby }}
-      - name: Install dependencies
-        run: bundle install
-      - name: Run tests
-        run: bundle exec rake
+          bundler-cache: true
+      - run: bundle exec rake