Move windows engine_v2 to prod. (flutter/engine#37680)

Windows engine_v2 are now generating the expected artifacts and ready to
be moved to the production environment.

Bug: https://github.com/flutter/flutter/issues/81855

engine/src/flutter/.ci.yaml

@@ -477,7 +477,6 @@ targets:
 
   - name: Windows windows_android_aot_engine
     recipe: engine_v2/engine_v2
-    bringup: true
     timeout: 60
     properties:
       release_build: "true"
@@ -485,7 +484,6 @@ targets:
 
   - name: Windows windows_host_engine
     recipe: engine_v2/engine_v2
-    bringup: true
     timeout: 60
     properties:
       release_build: "true"