[PATCH] docs: mention MyFirstContribution in more places

[Emily Shaffer <emilyshaffer@google.com>]

While the MyFirstContribution guide exists and has received some use and
positive reviews, it is still not as discoverable as it could be. Add a
reference to it from the GitHub pull request template, where many
brand-new contributors may look. Also add a reference to it in
SubmittingPatches, which is the central source of guidance for patch
contribution.

Signed-off-by: Emily Shaffer <emilyshaffer@google.com>
---
Philippe mentioned out-of-band that they wished for some more pointers
to MyFirstContribution in the Git documentation
(https://github.com/git/git-scm.com/issues/1464#issuecomment-631757274).

Here's a first pass. The change for the GH PR template was easy, since
there are a couple other "here's how" resources listed the same way. But
the change for SubmittingPatches I wasn't so sure about. Since that
document dives right into technical details and doesn't feature some
"other resources" section (at least not that I found), I made a quick
reference at the top, which I was hoping would be unintrusive but also
easy to find for newbies overwhelmed by the large list of rules. It's
not very scalable if we want to add more info, though, so I'm open to
other suggestions.

 - Emily

 .github/CONTRIBUTING.md         | 3 +++
 Documentation/SubmittingPatches | 5 +++--
 2 files changed, 6 insertions(+), 2 deletions(-)

diff --git a/.github/CONTRIBUTING.md b/.github/CONTRIBUTING.md
index e7b4e2f3c2..c8755e38de 100644
--- a/.github/CONTRIBUTING.md
+++ b/.github/CONTRIBUTING.md
@@ -16,4 +16,7 @@ If you prefer video, then [this talk](https://www.youtube.com/watch?v=Q7i_qQW__q
 might be useful to you as the presenter walks you through the contribution
 process by example.
 
+Or, you can follow the ["My First Contribution"](https://git-scm.com/docs/MyFirstContribution)
+tutorial for another example of the contribution process.
+
 Your friendly Git community!
diff --git a/Documentation/SubmittingPatches b/Documentation/SubmittingPatches
index 4515cab519..d8c6b4d71b 100644
--- a/Documentation/SubmittingPatches
+++ b/Documentation/SubmittingPatches
@@ -3,8 +3,9 @@ Submitting Patches
 
 == Guidelines
 
-Here are some guidelines for people who want to contribute their code
-to this software.
+Here are some guidelines for people who want to contribute their code to this
+software. There is also an link:MyFirstContribution.html[interactive tutorial]
+available which covers many of these same guidelines.
 
 [[base-branch]]
 === Decide what to base your work on.
-- 
2.27.0.rc0.183.gde8f92d652-goog