Use double dash accordingly common format

Author: Morganov

book/B-embedding-git/sections/jgit.asc

@@ -128,7 +128,7 @@ Git git = new Git(repo);
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 The Git class has a nice set of high-level _builder_-style methods that can be used to construct some pretty complex behavior.
-Let's take a look at an example – doing something like `git ls-remote`:
+Let's take a look at an example -- doing something like `git ls-remote`:
 
 [source,java]
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