Add space after comma for placeholder text (#25931)

public/app/features/admin/UserListAdminPage.tsx

@@ -45,7 +45,7 @@ const UserListAdminPageUnConnected: React.FC<Props> = props => {
               <Input
                 width={40}
                 type="text"
-                placeholder="Search user by login,email or name"
+                placeholder="Search user by login, email or name"
                 tabIndex={1}
                 autoFocus={true}
                 value={props.query}