ci: Remove ubuntu trusty

It's far from being supported by ubuntu, and we don't need to support it
anymore now that the appimage is migrated to xenial + We get quicker
pipelines.

Signed-off-by: Linus Jahn <lnj@kaidan.im>
9 jobs for ci-remove-trusty in 38 minutes and 29 seconds (queued for 39 minutes and 35 seconds)
latest
Status Job ID Name Coverage
  Test
passed #28780
clazy

00:01:11

passed #28781
qmllint

00:00:20

 
  Build
passed #28784
archlinux

00:01:50

passed #28783
debian-sid

00:01:18

passed #28782
neon-bionic

00:01:41

 
  Deploy
passed #28787
android

00:09:05

passed #28785
linux-appimage

00:11:18

passed #28788
mac-osxcross

00:06:40

passed #28786
windows-mxe

00:05:01