Fix #415 translate omitted sentence

Author: networm

book/05-distributed-git/sections/maintaining.asc

@@ -292,7 +292,7 @@ $ git merge-base contrib master
 $ git diff 36c7db
 ----
 
-or, more concisely:
+或者，更简洁的形式：
 
 [source,console]
 ----