Configurable GitHub static context for statuses integration

What does this MR do?

This merge request adds configurable static context support for GitHub status checks integration.

What are the relevant issue numbers?

Closes #6696 (moved)

Does this MR meet the acceptance criteria?

• Changelog entry added, if necessary
• Documentation created/updated
• Tests added for this feature/bug
• Conforms to the code review guidelines
• Conforms to the style guides
• EE specific content should be in the top level /ee folder