settings: Use "Label" consistently for custom profile field label.

We use Label as the heading for the field label column in the custom profile
fields table; but for some reason the edit UI called this "Name" instead.

Fixes #21260.

static/templates/settings/admin_profile_field_list.hbs

@@ -28,7 +28,7 @@
     <td colspan="3">
         <form class="form-horizontal name-setting">
             <div class="input-group">
-                <label for="name">{{t "Name" }}</label>
+                <label for="name">{{t "Label" }}</label>
                 <input type="text" name="name" value="{{ name }}" maxlength="40" />
             </div>
             <div class="input-group hint_change_container">