Prepare matrix in arrange job for reuse across build and assertion jobs

Co-authored-by: neilime <314088+neilime@users.noreply.github.com>
Signed-off-by: Emilien Escalle <emilien.escalle@escemi.com>

Author: Copilot

.github/workflows/__main-ci.yml

@@ -37,9 +37,7 @@ jobs:
     with:
       images: |
         [
-          "application-test",
-          "test-multi-arch",
-          "test-mono-arch"
+          "application-test"
         ]
 
   clean-with-cache: