Update how e2e tests work with nohup

Author: bitterpanda63

.github/workflows/end2end.yml

@@ -74,8 +74,7 @@ jobs:
       - name: Start Application (with and without Zen)
         working-directory: ./sample-apps/${{ matrix.app.name }}
         run: |
-          nohup make run > output.log 2>&1 &
-          nohup make runWithoutZen > output_without_zen.log 2>&1 &
+          nohup make run > output.log 2>&1 && nohup make runWithoutZen > output_without_zen.log 2>&1    
 
       - name: Run End-to-End tests
         working-directory: ./