feat: introduce qtkeychain and cmark modules

This change allows Neochat to be built against custom versions of these 3rd party dependencies.
2 jobs for custom-libs-for-neochat in 2 minutes and 47 seconds (queued for 45 minutes and 12 seconds)
Status Job ID Name Coverage
  Test
passed #83927
smoke-test

00:02:12

passed #83926
unit-test

00:00:35