[PATCH 3/3] MyFirstContribution: drop PR description for GGG single-patch contributions

["Philippe Blain via GitGitGadget" <gitgitgadget@gmail.com>]

From: Philippe Blain <levraiphilippeblain@gmail.com>

By default, GitHub prefills the PR description using the commit message
for single-commit PRs. This results in a duplicate commit message below
the three-dash line if the contributor does not empty out the PR
description before submitting, which adds noise for reviewers.

Add a note to that effect in MyFirstContribution.txt.

This partly addresses:
https://github.com/gitgitgadget/gitgitgadget/issues/340

Signed-off-by: Philippe Blain <levraiphilippeblain@gmail.com>
---
 Documentation/MyFirstContribution.txt | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/Documentation/MyFirstContribution.txt b/Documentation/MyFirstContribution.txt
index 96da32f7cef..2ce51d8c82e 100644
--- a/Documentation/MyFirstContribution.txt
+++ b/Documentation/MyFirstContribution.txt
@@ -821,6 +821,14 @@ Adding the 'psuh' command
 Your PR's description will used as the body of the cover letter.
 include::MyFirstContribution-coverletter.txt[]
 
+NOTE: For single-patch contributions, your commit message should already be
+meaningful and explain at a high level the purpose (what is happening and why)
+of your patch, so you usually do not need any additional context. In that case,
+remove the PR description that GitHub automatically generates from your commit
+message (your PR description should be empty). If you do need to supply even
+more context, you can do so in that space and it will be appended to the email
+that GitGitGadget will send, separately from your commit message.
+
 When you're happy, submit your pull request.
 
 [[run-ci-ggg]]
-- 
gitgitgadget