ci: use the pkg-config.exe hosted by meson since sourceforge is flaky

7 jobs for master in 6 minutes and 3 seconds (queued for 2 seconds)
Status Job ID Name Coverage
  Build
passed #181336
fedora-x86_64-autotools

00:02:24

passed #181335
fedora-x86_64-meson

00:00:57

passed #181338
win32
msys2-mingw32-autotools

00:04:58

passed #181337
win32
msys2-mingw32-meson

00:02:03

passed #181339
win32
vs2017-x64-meson

00:03:30

 
  Deploy
passed #181340
pages

00:00:28

passed pages:deploy

00:00:00