MyFirstContribution: reference "The cover letter" in GitGitGadget section

The "Sending Patches via GitGitGadget" section mentions that the PR title and description will be used as the cover letter, but does not explain what is a cover letter or what should be included in it. Refer readers to the new "The cover letter" section added in a previous commit. Signed-off-by: Philippe Blain <levraiphilippeblain@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>

Philippe Blain committed May 12, 2022 at 23:43 UTC c2cd4b592f89c4d11570c815f80b1a45266e4939
1 file changed +6 -2
Documentation/MyFirstContribution.txt
+6 -2
@@ -899,8 +899,12 @@ https://github.com/gitgitgadget/git and open a PR either with the "New pull
899 request" button or the convenient "Compare & pull request" button that may
900 appear with the name of your newly pushed branch.
901
902 -Review the PR's title and description, as it's used by GitGitGadget as the cover
903 -letter for your change. When you're happy, submit your pull request.
902 +Review the PR's title and description, as they're used by GitGitGadget
903 +respectively as the subject and body of the cover letter for your change. Refer
904 +to <<cover-letter,"The cover letter">> above for advice on how to title your
905 +submission and what content to include in the description.
906 +
907 +When you're happy, submit your pull request.
908
909 [[run-ci-ggg]]
910 === Running CI and Getting Ready to Send