Update git submodules
- Update extensions/OATHAuth from branch 'REL1_39' to 677293735a7af514a2392ef762567a06bb71fa0c
- Merge "build: Update MediaWiki requirement to 1.39.0" into REL1_39
- build: Update MediaWiki requirement to 1.39.0
Change-Id: Ic8b9145b38eae30a14f045721210fe6deed1f92c