Add truncation for the environment dropdown

Dropdown was overlapping with other components
when its items were outgrowing its size.
This change is related to the Threat
Monitoring page

ee/app/assets/javascripts/threat_monitoring/components/threat_monitoring_filters.vue

@@ -56,7 +56,7 @@ export default {
           :id="$options.environmentFilterId"
           ref="environmentsDropdown"
           class="mb-0 d-flex"
-          toggle-class="d-flex justify-content-between"
+          toggle-class="d-flex justify-content-between text-truncate"
           :text="currentEnvironmentName"
           :disabled="isDisabled"
         >

ee/changelogs/unreleased/add_truncation_for_environment_dropdown.yml

+---
+title: Add truncation for the environment dropdown
+merge_request: 32267
+author:
+type: fixed