Redundant ')' in the Stop words' example (#2856)

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website/usage/_adding-languages/_language-data.jade

@@ -183,7 +183,7 @@ p
 
     back be became because become becomes becoming been before beforehand behind
     being below beside besides between beyond both bottom but by
-    """).split())
+    """.split())
 
 +infobox("Important note")
     |  When adding stop words from an online source, always #[strong include the link]