Reverts "Mark `windows_host_engine_test` flaky (#167419)" (#167425)

<!-- start_original_pr_link -->
Reverts: flutter/flutter#167419
<!-- end_original_pr_link -->
<!-- start_initiating_author -->
Initiated by: loic-sharma
<!-- end_initiating_author -->
<!-- start_revert_reason -->
Reason for reverting: Test should no longer be flaky now that
https://github.com/flutter/flutter/pull/167420 has landed.
<!-- end_revert_reason -->
<!-- start_original_pr_author -->
Original PR Author: matanlurey
<!-- end_original_pr_author -->

<!-- start_reviewers -->
Reviewed By: {jtmcdole}
<!-- end_reviewers -->

<!-- start_revert_body -->
This change reverts the following previous change:
See https://github.com/flutter/flutter/issues/167418.
<!-- end_revert_body -->

Co-authored-by: auto-submit[bot] <flutter-engprod-team@google.com>
diff --git a/engine/src/flutter/.ci.yaml b/engine/src/flutter/.ci.yaml
index ee38f5e..4909854 100644
--- a/engine/src/flutter/.ci.yaml
+++ b/engine/src/flutter/.ci.yaml
@@ -524,7 +524,6 @@
       - os=Windows
 
   - name: Windows windows_host_engine_test
-    bringup: true # Flaky https://github.com/flutter/flutter/issues/167418
     recipe: engine_v2/engine_v2
     timeout: 120
     properties: