Add XML doc inference opt-out control

[N-Olbert]

Summary of the changes (Less than 80 chars)

• Introduced GraphQLIgnoreXmlDocumentationAttribute to allow the developer to control XML documentation inference
• Adds analyzer HC0106 to warn if XML documentation is not enabled when inference is active (which is the default)

Closes #bugnumber (in this specific format)

This may introduce a merge conflict with #9000 for the tests; if so I’ll update whichever branch will be merged last.