meson: 0.9.1 release

This is only a bugfix release so we keep the 0.9 prefix.
4 jobs for 0_9 in 6 minutes and 44 seconds (queued for 15 seconds)
latest
Status Job ID Name Coverage
  Build
passed #5888703
alpine

00:04:12

passed #5888701
arch

00:06:15

passed #5888702
debian

00:06:13

passed #5888700
fedora

00:05:44

88.5%