Bump actions/checkout from 3 to 4 (#52)

Author: dependabot[bot]

.github/workflows/lint.yml

@@ -7,7 +7,7 @@ jobs:
     runs-on: ubuntu-latest
     name: Lint - Ruby 2.6
     steps:
-    - uses: actions/checkout@v3
+    - uses: actions/checkout@v4
     - name: Set up Ruby 2.6
       uses: ruby/setup-ruby@v1
       with:

.github/workflows/tests.yml

@@ -12,7 +12,7 @@ jobs:
 
     name: Specs - Ruby ${{ matrix.ruby-version }}
     steps:
-    - uses: actions/checkout@v3
+    - uses: actions/checkout@v4
     - name: Set up Ruby ${{ matrix.ruby-version }}
       uses: ruby/setup-ruby@v1
       with: