ci/nouveau: Move manual/nightly jobs to postmerge stage

Create a new stage called nouveau-postmerge and move the full and manual
jobs over there, to avoid entanglement with the pre-merge jobs.

Signed-off-by: Daniel Stone <daniels@collabora.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/30784>

.gitlab-ci.yml

@@ -152,6 +152,7 @@ stages:
   - intel
   - intel-postmerge
   - nouveau
+  - nouveau-postmerge
   - arm
   - broadcom
   - broadcom-postmerge

src/gallium/drivers/nouveau/ci/gitlab-ci-inc.yml

@@ -24,7 +24,7 @@
       when: on_success
 
 .nouveau-manual-rules:
-  stage: nouveau
+  stage: nouveau-postmerge
   extends: .no-auto-retry
   rules:
     - !reference [.test, rules]

src/nouveau/ci/gitlab-ci-inc.yml

@@ -26,7 +26,7 @@
       when: on_success
 
 .nvk-valve-manual-rules:
-  stage: nouveau
+  stage: nouveau-postmerge
   extends: .no-auto-retry
   rules:
     - !reference [.test, rules]