Remove trailing whitespace from new users' usernames (#6528)

* Add input validation and error toast when attempting to add a new user with whitespaces at beginning or end.

* Update from OR expression

* Remove changes to en-gb due to only allowing direct commits to en-us.

* Update to automatically trim instead of showing a message.

src/apps/dashboard/routes/users/add.tsx

@@ -111,8 +111,9 @@ const UserNew = () => {
 
         const saveUser = () => {
             const userInput: UserInput = {};
-            userInput.Name = (page.querySelector('#txtUsername') as HTMLInputElement).value;
+            userInput.Name = (page.querySelector('#txtUsername') as HTMLInputElement).value.trim();
             userInput.Password = (page.querySelector('#txtPassword') as HTMLInputElement).value;
+
             window.ApiClient.createUser(userInput).then(function (user) {
                 if (!user.Id || !user.Policy) {
                     throw new Error('Unexpected null user id or policy');