remove unnecessary code

apps/app/src/components/PageControls/SeenUserInfo.tsx

@@ -2,7 +2,6 @@ import type { FC } from 'react';
 import React, { useState } from 'react';
 
 import type { IUser } from '@growi/core';
-import { FootstampIcon } from '@growi/ui/dist/components';
 import { useTranslation } from 'next-i18next';
 import { UncontrolledTooltip, Popover, PopoverBody } from 'reactstrap';
 
@@ -40,7 +39,7 @@ const SeenUserInfo: FC<Props> = (props: Props) => {
           </div>
         </PopoverBody>
       </Popover>
-      <UncontrolledTooltip data-testid="seen-user-info-tooltip" placement="top" target="btn-seen-user" fade={false}>
+      <UncontrolledTooltip data-testid="seen-user-info-tooltip" placement="bottom" target="btn-seen-user" fade={false}>
         {t('tooltip.footprints')}
       </UncontrolledTooltip>
     </div>