Pipeline tests simplification (#1348)

.github/workflows/composites/maven-build-with-dry-run-for-tests/action.yaml

@@ -0,0 +1,20 @@
+name: maven-build-with-dry-run-for-tests
+description: maven-build-with-dry-run-for-tests
+runs:
+  using: "composite"
+  steps:
+    - name: maven-build-with-dry-run-for-tests
+      shell: bash
+      run: |
+          # find all the tests that are supposed to be run, but don't actually run them.
+          # this is achieved via: 'spring.cloud.k8s.skip.tests=true' in DisabledTestsCondition
+          ./mvnw clean install -Dskip.build.image=true -Dspring.cloud.k8s.skip.tests=true \
+                -Dorg.slf4j.simpleLogger.log.org.apache.maven.cli.transfer.Slf4jMavenTransferListener=error \
+                -T 1C > /tmp/tests.txt
+
+    - name: upload test
+      uses: actions/upload-artifact@v3
+      with:
+        name: tests.txt
+        path: /tmp/tests.txt
+