Update CI instructions

Author: joeyates

.github/workflows/main.yml

@@ -29,7 +29,7 @@ jobs:
         rubygems: 3.0.3
         bundler-cache: true
     - name: Run the default task
-      run: bundle exec rake
+      run: bundle exec rake test
     - name: Read Coverage
       run: |
         echo "COVERAGE=$(cat coverage/coverage_percent.txt)%" >> $GITHUB_ENV