documentation: add missing parenthesis

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Signed-off-by: Elijah Newren <newren@gmail.com>

Author: newren

Documentation/git-remote-fd.txt

@@ -19,7 +19,7 @@ If only <infd> is given, it is assumed to be a bidirectional socket connected
 to a remote Git server (git-upload-pack, git-receive-pack, or
 git-upload-archive). If both <infd> and <outfd> are given, they are assumed
 to be pipes connected to a remote Git server (<infd> being the inbound pipe
-and <outfd> being the outbound pipe.
+and <outfd> being the outbound pipe).
 
 It is assumed that any handshaking procedures have already been completed
 (such as sending service request for git://) before this helper is started.