Merge pull request #1536 from HonkingGoose/patch-1

Fix highlighted text in AsciiDoctor 2 migration branch.

Author: jnavila

book/06-github/sections/2-contributing.asc

@@ -303,8 +303,8 @@ It turns out there are many, many ways to reference other things almost anywhere
 
 Let's start with how to cross-reference another Pull Request or an Issue.
 All Pull Requests and Issues are assigned numbers and they are unique within the project.
-For example, you can't have Pull Request #3 _and_ Issue #3.
-If you want to reference any Pull Request or Issue from any other one, you can simply put `#<num>` in any comment or description.
+For example, you can't have Pull Request +#3+ _and_ Issue +#3+.
+If you want to reference any Pull Request or Issue from any other one, you can simply put `+#<num>+` in any comment or description.
 You can also be more specific if the Issue or Pull request lives somewhere else; write `username#<num>` if you're referring to an Issue or Pull Request in a fork of the repository you're in, or `username/repo#<num>` to reference something in another repository.
 
 Let's look at an example.