6.12.1-rc2

Changes since rc1:

• EZP-28176: Fix SQL error on indexing with --subtree argument (#2152)
• EZP-28210: Logout not working when session cookie domain set (#2155)

Misc:

• Remove some deprecations on Symfony 3.4 (#2156)
• Change getMock to createMock in RememberMeRepositoryAuthenticationPro (12023ad)