changelog: mention the recent hg next fixes

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branch : stable
8 jobs for topic/stable/topic-next in 7 minutes and 11 seconds (queued for 2 seconds)
Status Job ID Name Coverage
  Test
passed checks-py2 #188994

00:01:24

passed checks-py3 #188995

00:01:39

passed doc #189000

00:00:32

manual pytype #188993
allowed to fail manual
passed tests-py2-cext #188996

00:05:06

passed tests-py2-pure #188997

00:04:01

passed tests-py3-cext #188998

00:07:10

passed tests-py3-pure #188999

00:07:00