Remove linux fuchsia from recipes cq. (#46153)

With some recent changes led builds can only run if they use -real-build. The migration of fuchsia builds to use -real-build as involved as migrating it to engine v2 and we are implementing the second one.

[C++, Objective-C, Java style guides]: https://github.com/flutter/engine/blob/main/CONTRIBUTING.md#style

.ci.yaml

@@ -161,7 +161,6 @@ targets:
   - name: Linux Fuchsia
     recipe: engine/engine
     properties:
-      add_recipes_cq: "true"
       build_fuchsia: "true"
       fuchsia_ctl_version: version:0.0.27
       # ensure files from pre-production Fuchsia SDK tests are purged from cache