settings: Fix data export spinner size.

This commit adds the same styles to the data export loader as we have
for the users table loader, ensuring that the spinner is sized
correctly and maintains consistency across the tables we have in
settings panel.

web/styles/settings.css

@@ -349,6 +349,7 @@ select.settings_select {
     word-break: normal;
 }
 
+.export_url_spinner,
 .last_active {
     .loading_indicator_spinner {
         width: 1.25em;