FastEndpoints 4.0.0-beta6

• net6.0

  • FluentValidation (>= 10.4.0)

### BREAKING CHANGES
           - PR #70 fluentvalidation code is no longer integrated. remove the package reference to `FastEndpoints.Validation` from your csproj file and add a `global using FluentValidation`. no other changes are necessary.
           - PR #68 `SerializerContext[T]()` has been removed. use the `SerializerContext(myContext.Default)` and provide the serializer context yourself.
           - the `Describe()` method has been removed. use `Description()` isntead. refer to the [doc page](https://fast-endpoints.com/wiki/Swagger-Support.html#describe-endpoints) for details. to migrate your existing code, just rename `Describe(...)` to `Description(..., clearDefaults: true)`
           - removed a previously deprecated `Summary()` overload. use one of the other `Summary()` methods if you were using the deprecated method.

           ### NEW
           - `Configure()` method is now optional. endpoint classes can be annotated with `[HttpGet("xyz")]`,`[AllowAnonymous]`,`[Authorize(Roles="abc")]` instead if that's preferred. Advanced usage however does require `Configure()` method.
           - `SendEventStream()` method for doing server-sent-events streams
           - `DontAutoTag()` method for ignoring auto swagger tagging based on path segment
           - `[QueryParam]` attribute for marking/describing request dto properties which are to be bound from query parameters.
           - PR #73 `Query[T]("xyz")` endpoint method for reading query params without a request dto

           ### FIXES
           - #65 with serializer ctx not being set correctly
           - #69 swagger not removing json properties correctly

           ### IMPROVEMENTS
           - nswag now uses the same serializer settings as fastendpoints by default, which is overrideable.