Remove non-existent directory from glob

Release-Notes: skip
Change-Id: I06dc7fec87608a36f538adae8a044491e2af0ce4
diff --git a/polygerrit-ui/app/BUILD b/polygerrit-ui/app/BUILD
index d94c10c..9811e14 100644
--- a/polygerrit-ui/app/BUILD
+++ b/polygerrit-ui/app/BUILD
@@ -12,7 +12,6 @@
     "constants",
     "elements",
     "embed",
-    "gr-diff",
     "mixins",
     "models",
     "scripts",