chore: nit fix

Nitpick, can we have consistent naming for method? As all others are
deleteX, rename to deleteGroups

Author: tdeleanu

lib/Services/cayenne.js

@@ -162,11 +162,11 @@ class Cayenne extends Request {
   }
 
   /**
-   * Destroys all groups and attributes for a user
+   * Delete all groups and attributes for a user
   * @param {string} applicationId
    * @param {string} userId The user id of the user that owns the parent device
    */
-  destroyGroups(applicationId, userId) {
+  deleteGroups(applicationId, userId) {
     const path = `/things/groups`;
     const query = this.setTenant(applicationId, userId);
     return this.send('DELETE', path, { query });