Update copilot-instructions.md

Follow dotnet/docs#47550

Author: IEvangelist

.github/copilot-instructions.md

@@ -1,3 +1,5 @@
+When you're assigned an issue, after you've completed your work and the workflows (status checks) have run, check to make sure there are no build warnings under the OpenPublishing.Build status check. If there are, open the build report (under View Details) and resolve any build warnings you introduced.
+
 When writing documentation or editing .md files, follow the following guidelines:
 
 Unless otherwise specified, all .NET content refers to modern .NET (not .NET Framework).
@@ -38,4 +40,4 @@ If you're assigned a GitHub issue that's labeled "breaking-change", include the
 
 If you include a code snippet that's more than 6 lines long, put it in a separate .cs file in a folder named "snippets" in the same folder as the document. Within the "snippets" folder, add a new directory with the name of the document. For example, if the document is named "my-doc.md", create a folder named "snippets/my-doc" folder. Also add a simple .csproj file to the same directory that targets the latest version of .NET. It can be a library or executable project.
 
-If you're adding a new Markdown file, it should be named in all lowercase with hyphens separating words. Also, omit any filler words such as "the" or "a" from the file name.
+If you're adding a new Markdown file, it should be named in all lowercase with hyphens separating words. Also, omit any filler words such as "the" or "a" from the file name.