use .ruby-version to test with instead of setting a value

.github/workflows/lint-and-test.yaml

@@ -7,8 +7,6 @@ jobs:
       - uses: actions/checkout@v4
       - name: Setup Ruby
         uses: ruby/setup-ruby@v1
-        with:
-          ruby-version: 2.6
       - name: Install dependencies
         run: |
           bundle install --jobs 4 --retry 3
@@ -20,8 +18,6 @@ jobs:
     steps:
       - uses: actions/checkout@v4
       - uses: ruby/setup-ruby@v1
-        with:
-          node-version: 2.1
       - name: Install dependencies
         run: |
           bundle install --jobs 4 --retry 3