ci/debian-build-testing: drop extra nesting section

`.gitlab-ci/meson/build.sh` already prints sections, having an extra one
here just means that nothing is visible by default.

Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/29113>
(cherry picked from commit d428cc1116)

.gitlab-ci/build/gitlab-ci.yml

@@ -190,7 +190,7 @@ debian-build-testing:
     .gitlab-ci/run-shellcheck.sh
     section_switch yamllint "yamllint"
     .gitlab-ci/run-yamllint.sh
-    section_switch meson "meson"
+    section_end
     .gitlab-ci/meson/build.sh
     .gitlab-ci/prepare-artifacts.sh
   timeout: 15m

.pick_status.json

@@ -19484,7 +19484,7 @@
         "description": "ci/debian-build-testing: drop extra nesting section",
         "nominated": false,
         "nomination_type": 3,
-        "resolution": 4,
+        "resolution": 1,
         "main_sha": null,
         "because_sha": null,
         "notes": null