build: Use install_data() to rename icons

Since 0.46.0, Meson allows renaming files when installing them. This is
useful to replace any workarounds to achieve the same (namely, the
icons).
1 job for fix-generated-source-dependency in 9 minutes and 28 seconds (queued for 6 seconds)
Status Job ID Name Coverage
  Test
passed #27655
flatpak

00:09:28