gitlab-ci: add meson JUnit test result into report

This allows the gitlab UI to show the test results in different ways,
see doc:

  https://docs.gitlab.com/ee/ci/unit_test_reports.html#how-it-works

Previous we only reports avocado test results (.avocado_test_job_template),
with this change, the qemu/meson tests are also covered.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20220525173411.612224-1-marcandre.lureau@redhat.com>
[AJB: expand the commit description]
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Message-Id: <20220527153603.887929-4-alex.bennee@linaro.org>

.gitlab-ci.d/buildtest-template.yml

@@ -44,6 +44,8 @@
     expire_in: 7 days
     paths:
       - build/meson-logs/testlog.txt
+    reports:
+      junit: build/meson-logs/testlog.junit.xml
 
 .avocado_test_job_template:
   extends: .common_test_job_template