Rate and Concurrency limiting middleware

[JunTaoLuo]

Part of Epic: https://github.com/dotnet/aspnetcore/issues/27464,

This tracks the work to create a middleware that will use the primitives designed in the epic.

Some design considerations:

• Support both rate and concurrency limits
• Bucketing limiters, e.g. for IP
• Endpoint awareness
  • Fallback: Default limiter or None
  • Attributes for endpoints
• Wait behaviours
  • NoWait
  • Stack (drop oldest on full)
  • Queue (drop incoming on full)
• Limiter policies (in the style of authz)
  • Config driven policies
  • Stringy for shared policies
  • Ad-hoc policies
• Sunset policy of ConcurrencyLimiter

[ghost]

We've moved this issue to the Backlog milestone. This means that it is not going to be worked on for the coming release. We will reassess the backlog following the current release and consider this item at that time. To learn more about our issue management process and to have better expectation regarding different types of issues you can read our Triage Process.

[wtgodbe]

Closing as done: https://github.com/dotnet/aspnetcore/tree/main/src/Middleware/RateLimiting