chore(Documentation/api): remove some whitespace

Documentation/api.md

@@ -357,7 +357,6 @@ curl -X GET http://127.0.0.1:4001/v2/keys/dir/asdf\?consistent\=true\&wait\=true
 }
 ```
 
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 ### Atomic Compare-and-Swap (CAS)
 
 Etcd can be used as a centralized coordination service in a cluster and `CompareAndSwap` is the most basic operation used to build a distributed lock service.
@@ -585,7 +584,6 @@ curl -L http://127.0.0.1:4001/v2/keys/dir?recursive=true -XDELETE
 }
 ```
 
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 ### Creating a hidden node
 
 We can create a hidden key-value pair or directory by add a `_` prefix.