ci: Fix stage of etnaviv manual runs.

Fixes: f6c06ef2f6 ("ci: Add manual rules variations to disable irrelevant driver jobs.")
Acked-by: Mike Blumenkrantz <michael.blumenkrantz@gmail.com>
Acked-by: Eric Engestrom <eric@igalia.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/21366>

.gitlab-ci/test-source-dep.yml

@@ -851,7 +851,7 @@
       when: on_success
 
 .etnaviv-manual-rules:
-  stage: intel
+  stage: etnaviv
   rules:
     - !reference [.gl-manual-rules, rules]
     - changes: