[etwist] remove no-longer-necessary uicache cleaning
It was done before we were actually up, which means it could be too
eager when combined with #6893185.
Closes #6893247.
if versions_map['cubicweb'][0] == (3, 7, 4):
config['http-session-time'] *= 60
config['cleanup-session-time'] *= 60
config['cleanup-anonymous-session-time'] *= 60