Add issue count for each of the project's tabs

[ryansheehan]

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Product Feedback

Select Feature Area

• Issues
• Projects

Body

Best described by the screenshot below; it would be really useful to see each tab's issue count. That way, we would not necessarily have to open a tab to get a sense of what is going on within the overall project.

Guidelines

• I have read the above statement and can confirm my post is relevant to the GitHub feature areas Issues and/or Projects.