Update commit message recommendations

Author: AA-Turner

doc/internals/contributing.rst

@@ -121,16 +121,7 @@ These are the basic steps needed to start developing on Sphinx.
 
    .. code-block:: shell
 
-      git commit -m '#42: Add useful new feature that does this.'
-
-   GitHub recognizes certain phrases that can be used to automatically
-   update the issue tracker. For example:
-
-   .. code-block:: shell
-
-      git commit -m 'Closes #42: Fix invalid markup in docstring of Foo.bar.'
-
-   would close issue #42.
+      git commit -m 'Add useful new feature that does this.'
 
 #. Push changes in the branch to your forked repository on GitHub:
 
@@ -140,6 +131,11 @@ These are the basic steps needed to start developing on Sphinx.
 
 #. Submit a pull request from your branch to the ``master`` branch.
 
+   GitHub recognizes certain phrases that can be used to automatically
+   update the issue tracker.
+   For example, including 'Closes #42' in the body of your pull request
+   will close issue #42 if the PR is merged.
+
 #. Wait for a core developer or contributor to review your changes.