ci: remove build-ci-builder dependency from check/test (image exists in SCR)

.gitlab-ci.yml

@@ -52,14 +52,12 @@ build-ci-builder:
       --destination "${CI_BUILDER_IMAGE}"
 
 # Base template for Rust jobs — pre-baked CI builder from Scaleway CR
+# Image pre-exists in SCR; rebuild via build-ci-builder when Dockerfile changes
 .rust-base:
   image: ${CI_BUILDER_IMAGE}
   tags:
     - kapsule
     - rust
-  needs:
-    - job: build-ci-builder
-      optional: true
 
 # --------------------------------------------------------------------------
 # Stage 1: cargo check + clippy
@@ -79,10 +77,7 @@ check:
 test:
   extends: .rust-base
   stage: test
-  needs:
-    - job: build-ci-builder
-      optional: true
-    - check
+  needs: [check]
   script:
     - cargo test --workspace --lib