CI: Use templates to prepare the images used for the monthly build

Probably we can eventually replace the monthly build altogether with CI
templates, but this at least produces images with the correct packages
pre-installed for building those monthly images.
14 jobs for bye-dockerhub in 6 minutes and 31 seconds
Status Job ID Name Coverage
  Prepare
passed #999338
build-alpine-image

00:00:10

 
  Source Check
passed #999339
build_recommended

00:00:57

passed #999340
iwyu

00:00:36

 
  Test
passed #999342
build_maximal

00:05:07

passed #999343
build_minimal

00:05:23

passed #999341
asan
sanitizer_gcc

00:01:23

 
  Manual
manual #999344
allowed to fail manual
coverage
manual #999347
allowed to fail manual
installed_tests
manual #999345
allowed to fail manual
iwyu-full
manual #999346
asan allowed to fail manual
sanitizer_clang
manual #999348
allowed to fail manual
valgrind
manual #999351
allowed to fail manual
zeal_11
manual #999349
allowed to fail manual
zeal_2
manual #999350
allowed to fail manual
zeal_4