Fix a typo in GN documentation

This CL fixes the typo introduced in r439541.

Review-Url: https://codereview.chromium.org/2591863002
Cr-Original-Commit-Position: refs/heads/master@{#439891}
Cr-Mirrored-From: https://chromium.googlesource.com/chromium/src
Cr-Mirrored-Commit: a8936b7a13ff687bb186db70681723bf8b6bd531

tools/gn/docs/reference.md

diff --git a/tools/gn/docs/reference.md b/tools/gn/docs/reference.md
index 26ba5c6..b62abbd 100644
--- a/tools/gn/docs/reference.md
+++ b/tools/gn/docs/reference.md
@@ -6584,7 +6584,7 @@
       build.gn file.
         "//foo/bar/baz.txt" => "obj/foo/bar"
 
-  {{source_target_relative}}\n"
+  {{source_target_relative}}
       The path to the source file relative to the target's directory. This will
       generally be used for replicating the source directory layout in the
       output directory. This can only be used in actions and it is an error to

tools/gn/substitution_writer.cc

diff --git a/tools/gn/substitution_writer.cc b/tools/gn/substitution_writer.cc
index 7a3534e..50b1e2d 100644
--- a/tools/gn/substitution_writer.cc
+++ b/tools/gn/substitution_writer.cc
@@ -98,7 +98,7 @@
       build.gn file.
         "//foo/bar/baz.txt" => "obj/foo/bar"
 
-  {{source_target_relative}}\n"
+  {{source_target_relative}}
       The path to the source file relative to the target's directory. This will
       generally be used for replicating the source directory layout in the
       output directory. This can only be used in actions and it is an error to