Remove the used comma

Atry · web-flow · commit 449bddef7f5d · 2018-12-01T01:14:26.000+08:00
diff --git a/_style/naming-conventions.md b/_style/naming-conventions.md
@@ -12,7 +12,7 @@ next-page: types
 ---
 
 Generally speaking, Scala uses "camel case" naming. That is,
-each word, is capitalized, except possibly the first word:
+each word is capitalized, except possibly the first word:
 
     UpperCamelCase
     lowerCamelCase
