Cache dependencies using ruby/setup-ruby

To speed our CI a bit, let's cache the dependencies.
I am using the recommended cache strategy for Ruby:
https://github.com/actions/cache/blob/main/examples.md#ruby---bundler

Additionally, to use the without configuration, we need to explicitely
use the configuration keys through the environment:
https://bundler.io/man/bundle-config.1.html#CONFIGURATION-KEYS

Author: stefannibrasil

.github/workflows/bench.yml

@@ -19,8 +19,7 @@ jobs:
     - uses: ruby/setup-ruby@v1
       with:
         ruby-version: '4.0'
-    - name: Install dependencies
-      run: bundle install
+        bundler-cache: true
 
     - name: Generators
       run: RUBYOPT="-W0" bundle exec ruby benchmark/generators.rb

.github/workflows/ruby.yml

@@ -21,20 +21,22 @@ jobs:
   lint:
     name: RuboCop
     runs-on: ubuntu-latest
+    env:
+      BUNDLE_WITHOUT: benchmark
     steps:
       - uses: actions/checkout@v6
       - uses: ruby/setup-ruby@v1
         with:
           ruby-version: '4.0'
-
-      - name: Install dependencies
-        run: bundle install
+          bundler-cache: true
 
       - name: Run RuboCop
         run: bundle exec rake rubocop
   test:
     name: Ruby ${{ matrix.ruby }}
     runs-on: ubuntu-latest
+    env:
+      BUNDLE_WITHOUT: benchmark
     strategy:
       fail-fast: false # don't fail all matrix builds if one fails
       matrix:
@@ -52,11 +54,7 @@ jobs:
     - uses: ruby/setup-ruby@v1
       with:
         ruby-version: ${{ matrix.ruby }}
-
-    - name: Install dependencies
-      run: |
-        bundle config set --without benchmark
-        bundle install
+        bundler-cache: true
 
     - name: Run tests
       run: bundle exec rake test