Update git submodules
- Update extensions/SyntaxHighlight_GeSHi from branch 'REL1_39' to 621125bf429f80305ea44f90d579f9140a9214dc
- Localisation updates from https://translatewiki.net.
Change-Id: Ifaf26df21da305423034199d9dcd73f55e7265b2
- Localisation updates from https://translatewiki.net.