Provide code analysis rule to detect attribute routing for non-action methods

[Alex-Sob]

This PR should address #56791

This PR is adding a new code analysis rule ASP0029: Attribute routing is used for a method that is not an action. The diagnostic should be reported for a controller method if the following conditions are met:

• The method is not an action, e.g. it's not public or marked with [NonAction] attribute.
• Attribute routing is used for that method, e.g. it's marked with [Route] or [Http{Method}] or [AcceptVerbs] attributes.

Changes

• Modified MvcAnalyzer so that it checks non-action methods of a controller to see if a method is marked with an attribute that implements IRouteTemplateProvider. In such a case it reports ASP0029 diagnostic.

• Added basic unit tests, I could add more if PR is accepted for review.

  I used the same approach for unit tests here that I suggested separately in [Proposal] Performance/usability improvements for analyzer tests #63684