meson: remove outdated fixme

2 jobs for master in 1 minute and 4 seconds (queued for 2 seconds)
Status Job ID Name Coverage
  Lint
passed #250422
rustfmt

00:00:34

 
  Test
failed #250423
flatpak

00:00:29

 
Name Stage Failure
failed
flatpak Test
Cloning into '/builds/World/podcasts'...
Checking out 82c99e2c as master...
Skipping Git submodules setup
Checking cache for flatpak-17...
No URL provided, cache will not be downloaded from shared cache server. Instead a local version of cache will be extracted.
Successfully extracted cache
$ flatpak-builder --stop-at=${FLATPAK_MODULE} app ${MANIFEST_PATH}
Can't load 'org.gnome.PodcastsDevel.json': Failed to open file ?/builds/World/podcasts/org.gnome.PodcastsDevel.json?: No such file or directory
ERROR: Job failed: exit code 1