[Search] Update "Connectors" search type to singular "Connector" (#18…

…2006)

## Summary

Update search tag from "Connectors" to "Connector"

### Checklist

Delete any items that are not applicable to this PR.

- [ ] [Unit or functional
tests](https://www.elastic.co/guide/en/kibana/master/development-tests.html)
were updated or added to match the most common scenarios

(cherry picked from commit 005f11c)

x-pack/plugins/enterprise_search/server/utils/connectors_search_result_provider.ts

@@ -26,7 +26,7 @@ export function getConnectorsSearchResultProvider(
 ): GlobalSearchResultProvider {
   return {
     find: ({ term, types, tags }, { aborted$, client, maxResults }) => {
-      if (!client || !term || tags || (types && !types.includes('connectors'))) {
+      if (!client || !term || tags || (types && !types.includes('connector'))) {
         return from([[]]);
       }
       const getConnectorData = async (): Promise<GlobalSearchProviderResult[]> => {
@@ -54,7 +54,7 @@ export function getConnectorsSearchResultProvider(
       };
       return from(getConnectorData()).pipe(takeUntil(aborted$));
     },
-    getSearchableTypes: () => ['connectors'],
+    getSearchableTypes: () => ['connector'],
     id: 'enterpriseSearchConnectors',
   };
 }