Extract build task into separate step.

Author: ioquatix

.github/workflows/test-external.yaml

@@ -33,16 +33,20 @@ jobs:
         ruby-version: ${{matrix.ruby}}
         bundler-cache: true
 
+    - name: Build extensions
+      timeout-minutes: 10
+      run: bundle exec bake build
+    
     - name: Run tests
       timeout-minutes: 10
-      run: bundle exec bake build test:external
+      run: bundle exec bake test:external
 
     - name: Run tests (worker pool)
       if: ${{matrix.os == 'ubuntu' && matrix.ruby == 'head'}}
       env:
         ASYNC_SCHEDULER_WORKER_POOL: true
       timeout-minutes: 10
-      run: bundle exec bake build test:external
+      run: bundle exec bake test:external
 
     # - name: Run tests (pure Ruby)
     #   env: