Try to fix CI tests

Author: wvengen

.github/workflows/test.yml

@@ -59,6 +59,7 @@ jobs:
             pytest -vv --color=yes "$test"
             # stop scrapyd-k8s again
             kill %1
+            sleep 1
           done
 
   test-manifest:
@@ -195,4 +196,5 @@ jobs:
               pytest -vv --color=yes "$test"
             # stop scrapyd-k8s again
             kill %1
+            sleep 1
           done