Fix zero-padding in gerrit ref

infra/bots/recipe_modules/core/api.py

Index: infra/bots/recipe_modules/core/api.py
diff --git a/infra/bots/recipe_modules/core/api.py b/infra/bots/recipe_modules/core/api.py
index c851ed49a5f52b2c41e78eed6ad46bc92d0d5c00..74adf6afd088d3dece1d0b5f8ec01d8e1a6f4de7 100644
--- a/infra/bots/recipe_modules/core/api.py
+++ b/infra/bots/recipe_modules/core/api.py
@@ -116,8 +116,8 @@ class SkiaApi(recipe_api.RecipeApi):
     # Hack the patch ref if necessary.
     if self.m.properties.get('patch_storage', '') == 'gerrit':
       if self.m.bot_update._issue and self.m.bot_update._patchset:
-        self.m.bot_update._gerrit_ref = 'refs/changes/%d/%d/%d' % (
-            int(str(self.m.bot_update._issue)[-2:]),
+        self.m.bot_update._gerrit_ref = 'refs/changes/%s/%d/%d' % (
+            str(self.m.bot_update._issue)[-2:],
             self.m.bot_update._issue,
             self.m.bot_update._patchset,
         )