build: Bump Meson dependency to 0.52.0

This is what’s available in the new Debian Stable, so we can expect it
to be available pretty much everywhere.

Subsequent commits will clean up old workarounds.

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

.gitlab-ci.yml

@@ -441,7 +441,7 @@ macos:
   needs: []
   before_script:
     - bash .gitlab-ci/show-execution-environment.sh
-    - pip3 install --user meson==0.49.2
+    - pip3 install --user meson==0.52.0
     - pip3 install --user ninja
     - export PATH=/Users/gitlabrunner/Library/Python/3.7/bin:$PATH
   script: