Update git submodules

* Update TwoColConflict from branch 'master'
  to b3c8bf9a8e549b9f47df865311749a573ed1ac42
  - Merge "Consider third conflicting edits"
  - Consider third conflicting edits
    
    Edits done while solving a conflict should trigger a new conflict with
    the resolved version of the initial conflict on the yours side and the
    data of the conflicting third edit on the other side.
    
    This patch removes dead code that messed with the workflow in these cases.
    The removed code originally was added to allow going back to the current state
    of the conflict screen when using POST requests to trigger preview or diff.
    This is not done anymore so the code can completely be remove.
    
    This patch ( at least temporarly ) selects the other side by default now.
    
    We might add something similar again when dealing with non-JS handling of
    of the conflict.
    
    Bug: T245730
    Change-Id: Iba19d8fd1c372d1697a894b0ad1ccde8b4d84d16