gn: fix documentation typo

tools/gn/docs/reference.md

 # GN Reference
 
 *This page is automatically generated from* `gn help --markdown all`.
 
 ## **--args**: Specifies build arguments overrides.
 
 ```
   See "gn help buildargs" for an overview of how build arguments work.
 
   Most operations take a build directory. The build arguments are taken
@@ skipping 1431 matching lines @@
       The output file directory corresponding to the path of the
       given file, not including a trailing slash.
         "//foo/bar/baz.txt" => "//out/Default/obj/foo/bar"
   "gen_dir"
       The generated file directory corresponding to the path of the
       given file, not including a trailing slash.
         "//foo/bar/baz.txt" => "//out/Default/gen/foo/bar"
 
   "abspath"
       The full absolute path name to the file or directory. It will be
-      resolved relative to the currebt directory, and then the source-
+      resolved relative to the current directory, and then the source-
       absolute version will be returned. If the input is system-
       absolute, the same input will be returned.
         "foo/bar.txt" => "//mydir/foo/bar.txt"
         "foo/" => "//mydir/foo/"
         "//foo/bar" => "//foo/bar"  (already absolute)
         "/usr/include" => "/usr/include"  (already absolute)
 
       If you want to make the path relative to another directory, or to
       be system-absolute, see rebase_path().
 
@@ skipping 3361 matching lines @@
 **  --nocolor**: Force non-colored output.
 **  -q**: Quiet mode. Don't print output on success.
 **  --root**: Explicitly specify source root.
 **  --runtime-deps-list-file**: Save runtime dependencies for targets in file.
 **  --time**: Outputs a summary of how long everything took.
 **  --tracelog**: Writes a Chrome-compatible trace log to the given file.
 **  -v**: Verbose logging.
 **  --version**: Prints the GN version number and exits.
 
 ```