changed error text wording

public/language/en-GB/error.json

@@ -144,7 +144,7 @@
 	"not-enough-reputation-to-downvote": "You do not have enough reputation to downvote this post",
 	"not-enough-reputation-to-flag": "You do not have enough reputation to flag this post",
 	"already-flagged": "You have already flagged this post",
-	"self-vote": "You cannot upvote/downvote your own post",
+	"self-vote": "You cannot vote on your own post",
 
 	"reload-failed": "NodeBB encountered a problem while reloading: \"%1\". NodeBB will continue to serve the existing client-side assets, although you should undo what you did just prior to reloading.",