chore: add checkout action before spell check

Author: soumyamahunt

.github/workflows/main.yml

@@ -37,10 +37,13 @@ jobs:
     name: Run spell check
     runs-on: ubuntu-latest
     steps:
-      - name: Spellcheck Action
-        uses: rojopolis/spellcheck-github-actions@0.24.0
-        with:
-          config_path: '.github/config/spellcheck.yml'
+    - name: Checkout repository
+      uses: actions/checkout@v3
+
+    - name: Spellcheck Action
+      uses: rojopolis/spellcheck-github-actions@0.24.0
+      with:
+        config_path: .github/config/spellcheck.yml
 
   swift-package-test:
     name: Run Swift Package Tests