Adding repository field to engine.proto

This field is necessary to create a generic
release builder recipe.

Bug:https://github.com/flutter/flutter/issues/115486
Change-Id: Id9aaa0a01ad1f93b5e8eaf9084eaac874ac5c5e7
Reviewed-on: https://flutter-review.googlesource.com/c/recipes/+/36722
Reviewed-by: Godofredo Contreras <godofredoc@google.com>
Commit-Queue: Godofredo Contreras <godofredoc@google.com>
diff --git a/recipes/engine/engine.proto b/recipes/engine/engine.proto
index b6f7ab0..35b2951 100644
--- a/recipes/engine/engine.proto
+++ b/recipes/engine/engine.proto
@@ -69,6 +69,8 @@
   // emulator architecture to run tests on
   // Currently only used by femu_test
   string emulator_arch = 32;
+
+  string repository = 33;
 }
 
 message EnvProperties {