ci: moves simplecov into validations

Author: bougyman

.github/workflows/validations.yaml

@@ -10,3 +10,12 @@ jobs:
   validate_ruby:
     name: Ruby Tests
     uses: ./.github/workflows/main.yaml
+  ensure_coverage:
+    needs: validate_ruby
+    steps:
+      - name: Check SimpleCov coverage
+        uses: joshmfrankel/simplecov-check-action@main
+        with:
+          minimum_suite_coverage: 97
+          minimum_file_coverage: 90
+          github_token: ${{ secrets.GITHUB_TOKEN }}