08ce33f8e qa: Move wait_until to util (MarcoFalke)
Pull request description:
This moves `wait_until` to `util.py` to make it generally available to python tests.
Also, `wait_until` now takes an optional lock that is acquired while testing the predicate.
Previously the lock was always acquired, even when it was not necessary, cf. `disconnect_ban.py`.
Tree-SHA512: 18e452a017a6566fa8ad09bde058e1b841e167039dc63299e70cfa7a6dcbc779581e60ca3e8eb2f1b610767d5208b9376c203eb11015b250fd0542b5eb4215a8
c9cc76d [tests] Remove is_network_split from funtional test cases (John Newbery)
Tree-SHA512: a43ec63a7dc20cbe9048f8d3af755aef55e9247f605d6481e6d665112882a749af7514f29c83ca9d761421b8e0f7282e5b9f8fc471985d222de826da7cc80ccf
Signed-off-by: Pasta <pasta@dashboost.org>