Add descriptions for endpoints for use in openapi

src/Vegasco.Server.Api/Cars/UpdateCar.cs

@@ -16,6 +16,7 @@ public static class UpdateCar
 		return builder
 			.MapPut("cars/{id:guid}", Endpoint)
 			.WithTags("Cars")
+			.WithDescription("Updates a car by ID")
 			.Produces<Response>()
 			.ProducesValidationProblem()
 			.Produces(404);