Fix robustness tests execution

Remove running the tests for all the packages under ./tests/robustness.
Restore the old behavior of running only the tests from the top-level
robustness package.

Signed-off-by: Ivan Valdes <ivan@vald.es>

scripts/test.sh

@@ -184,10 +184,10 @@ function e2e_pass {
 function robustness_pass {
   # e2e tests are running pre-build binary. Settings like --race,-cover,-cpu does not have any impact.
   KEEP_GOING_TESTS=true \
-    run_go_tests_expanding_packages ./tests/robustness/... \
-                                      -timeout="${TIMEOUT:-30m}" \
-                                      "${RUN_ARG[@]}" \
-                                      "$@"
+    run_go_tests ./tests/robustness/... \
+                   -timeout="${TIMEOUT:-30m}" \
+                   "${RUN_ARG[@]}" \
+                   "$@"
 }
 
 function integration_e2e_pass {