Merge ~schopin/britney/+git/hints-ubuntu:impish-mosquitto into ~ubuntu-release/britney/+git/hints-ubuntu:devel

[Simon Chopin]

diff --git a/ubuntu-release b/ubuntu-release
index c1e0b41..f725d56 100644
--- a/ubuntu-release
+++ b/ubuntu-release
@@ -285,6 +285,8 @@ force-reset-test micropython/1.12-2build1
 force-reset-test mmseqs2/9-d36de+ds-4/amd64
 ## regressed in release, https://bugs.debian.org/988836
 force-reset-test moment-timezone.js/0.5.32+dfsg1-1
+## REALLY flaky on s390x, occasional failure on amd64. See LP: #1929553
+force-badtest mosquitto/2.0.11-1/s390x
 ##
 force-reset-test mothur/1.42.1-1/i386
 ## LP: #1893671