PolyGerrit: Fix some typos

Change-Id: I7baa30a432e43565553cc62cc2b87dca3aae6357

polygerrit-ui/app/elements/change/gr-reply-dialog/gr-reply-dialog.ts

diff --git a/polygerrit-ui/app/elements/change/gr-reply-dialog/gr-reply-dialog.ts b/polygerrit-ui/app/elements/change/gr-reply-dialog/gr-reply-dialog.ts
index 705a402..a8e89b6 100644
--- a/polygerrit-ui/app/elements/change/gr-reply-dialog/gr-reply-dialog.ts
+++ b/polygerrit-ui/app/elements/change/gr-reply-dialog/gr-reply-dialog.ts
@@ -784,7 +784,7 @@
   }
 
   _handle400Error(r?: Response | null) {
-    if (!r) throw new Error('Reponse is empty.');
+    if (!r) throw new Error('Response is empty.');
     let response: Response = r;
     // A call to _saveReview could fail with a server error if erroneous
     // reviewers were requested. This is signalled with a 400 Bad Request