Fix policy_editor environment picker

- in https://gitlab.com/gitlab-org/gitlab/-/merge_requests/67419
  a Vuex action was changed and an instance of it was missed
  in updating

Changelog: fixed
EE: true

ee/app/assets/javascripts/threat_monitoring/policy_editor.js

@@ -25,9 +25,7 @@ export default () => {
   } = el.dataset;
 
   const store = createStore();
-  store.dispatch('threatMonitoring/setEndpoints', {
-    environmentsEndpoint,
-  });
+  store.dispatch('threatMonitoring/setEnvironmentEndpoint', environmentsEndpoint);
   store.dispatch('networkPolicies/setEndpoints', {
     networkPoliciesEndpoint,
   });