CI: temp disable t720/t760 jobs.

These are hanging somewhere.

Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/6335>
diff --git a/.gitlab-ci/lava-gitlab-ci.yml b/.gitlab-ci/lava-gitlab-ci.yml
index d5a51ce..4916904 100644
--- a/.gitlab-ci/lava-gitlab-ci.yml
+++ b/.gitlab-ci/lava-gitlab-ci.yml
@@ -149,7 +149,7 @@
   extends:
     - .lava-test:arm64
 
-panfrost-t720-gles2:arm64:
+.panfrost-t720-gles2:arm64:
   extends:
     - .lava-test:arm64
     - .panfrost-rules
@@ -161,7 +161,7 @@
   tags:
     - mesa-ci-aarch64-lava-collabora
 
-panfrost-t760-gles2:armhf:
+.panfrost-t760-gles2:armhf:
   extends:
     - .lava-test:armhf
     - .panfrost-rules