Move linux fuchsia engine v2 build to prod. (#41865)

This build has been running on prod for a few days already and it is ready to get moved to prod.

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

Author: godofredoc

.ci.yaml

@@ -140,6 +140,7 @@ targets:
     timeout: 60
 
   - name: Linux Fuchsia
+    bringup: true
     recipe: engine/engine
     properties:
       add_recipes_cq: "true"
@@ -256,7 +257,6 @@ targets:
     timeout: 90
 
   - name: Linux linux_fuchsia
-    bringup: true
     recipe: engine_v2/engine_v2
     timeout: 60
     properties: