ci: Enable JIT debugging on msys2-* CI jobs

Suggested by Christoph Reiter, this is a workaround for random Python
crashes in Meson which only appear on this platform.

It’s being tracked upstream at
msys2/MINGW-packages#11864, but unfortunately
it seems hard to fix.

Work around the issue the same way that Meson have in their CI, by
enabling JIT debugging. See
https://gitlab.gnome.org/GNOME/glib/-/merge_requests/3280#note_1678973.

Signed-off-by: Philip Withnall <pwithnall@endlessos.org>

.gitlab-ci.yml

@@ -325,6 +325,10 @@ msys2-mingw32:
     CHERE_INVOKING: "yes"
     CFLAGS: -coverage -ftest-coverage -fprofile-arcs
     PYTHONUTF8: "1"
+    # FIXME: For some reason enabling jit debugging "fixes" random python crashes
+    # see https://github.com/msys2/MINGW-packages/issues/11864 and
+    # https://gitlab.gnome.org/GNOME/glib/-/merge_requests/3280#note_1678973
+    MSYS: "winjitdebug"
   script:
     - C:\msys64\usr\bin\pacman --noconfirm -Syyuu --ask 20
     - C:\msys64\usr\bin\bash .gitlab-ci/show-execution-environment.sh
@@ -351,6 +355,10 @@ msys2-clang64:
     MSYSTEM: "CLANG64"
     CHERE_INVOKING: "yes"
     PYTHONUTF8: "1"
+    # FIXME: For some reason enabling jit debugging "fixes" random python crashes
+    # see https://github.com/msys2/MINGW-packages/issues/11864 and
+    # https://gitlab.gnome.org/GNOME/glib/-/merge_requests/3280#note_1678973
+    MSYS: "winjitdebug"
   script:
     - C:\msys64\usr\bin\pacman --noconfirm -Syyuu --ask 20
     - C:\msys64\usr\bin\bash .gitlab-ci/show-execution-environment.sh