Documentation: git-read-tree: separate links using commas

This makes it consistent with the rest of the documentation.

Signed-off-by: Nihal Jere <nihal@nihaljere.xyz>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

Documentation/git-read-tree.txt

@@ -420,8 +420,8 @@ support.
 
 SEE ALSO
 --------
-linkgit:git-write-tree[1]; linkgit:git-ls-files[1];
-linkgit:gitignore[5]; linkgit:git-sparse-checkout[1];
+linkgit:git-write-tree[1], linkgit:git-ls-files[1],
+linkgit:gitignore[5], linkgit:git-sparse-checkout[1]
 
 GIT
 ---