dialog: Drop a special case for GTK < 3.24.2

This avoids having multiple paths to debug but more importantly this
avoids having an altered API depending on the build environment as we
drop a reimplementation of the transient-for property in HdyDialog.
11 jobs for bump-gtk in 18 minutes and 55 seconds (queued for 25 minutes and 17 seconds)
Status Job ID Name Coverage
  Build
passed #256247
librem5
api-visibility

00:02:33

passed #256249
librem5
build-debian-clang

00:03:48

passed #256248
librem5
build-debian-gcc

00:02:45

passed #256250
librem5
build-fedora-gcc

00:05:07

 
  Test+Docs
passed #256251
librem5
build-gtkdoc

00:02:34

passed #256252
librem5
unit-test

00:02:29

43.7%
 
  Package
passed #256253
librem5
package-debian-buster

00:02:34

passed #256254
librem5:arm64
package-debian-buster:arm64

00:06:03

failed #256255
flatpak allowed to fail
package-flatpak

00:00:09

 
  Test Package
passed #256256
librem5
autopkgtest-debian-buster-package

00:02:32

passed #256257
librem5
lintian-debian-buster-package

00:01:04

 
Name Stage Failure
failed
package-flatpak Package There has been a runner system failure, please try again
Running with gitlab-runner 12.6.0 (ac8e767a)
on arm01-runner 53gNDtDb
ERROR: Preparation failed: Cannot connect to the Docker daemon at unix:///var/run/docker.sock. Is the docker daemon running? (executor_docker.go:982:0s)
Will be retried in 3s ...
ERROR: Preparation failed: Cannot connect to the Docker daemon at unix:///var/run/docker.sock. Is the docker daemon running? (executor_docker.go:982:0s)
Will be retried in 3s ...
ERROR: Preparation failed: Cannot connect to the Docker daemon at unix:///var/run/docker.sock. Is the docker daemon running? (executor_docker.go:982:0s)
Will be retried in 3s ...
ERROR: Job failed (system failure): Cannot connect to the Docker daemon at unix:///var/run/docker.sock. Is the docker daemon running? (executor_docker.go:982:0s)