[ticket/12379] Remove duplicate labels in attachment uploader when responsive.

PHPBB3-12379
Merge remote-tracking branch 'prototech/ticket/12379' into develop-ascraeus

* prototech/ticket/12379:
  [ticket/12379] Remove duplicate labels in attachment uploader when responsive.
Merge branch 'develop-ascraeus' into develop

* develop-ascraeus:
  [ticket/12379] Remove duplicate labels in attachment uploader when responsive.