Fix reference to 'double-dot'

Author: Ud Yzr

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

@@ -282,7 +282,7 @@ or, more concisely:
 $ git diff $(git merge-base contrib master)
 ----
 
-However, neither of those is particularly convenient, so Git provides another shorthand for doing the same thing: the ellipsis (double-dot) syntax.
+However, neither of those is particularly convenient, so Git provides another shorthand for doing the same thing: the double-dot syntax.
 In the context of the `git diff` command, you can put two periods after another branch to do a `diff` between the last commit of the branch you're on and its common ancestor with another branch:
 
 [source,console]