Dev: OutgoingRequestInterface is missing

[kenjis]

The current CI4 does not have Request interface for an outgoing request.

Problem:

• CURLRequest must implement methods for incoming requests that do not have to have.

http://www.plantuml.com/plantuml/uml/ZPBD3i8W48JlFCN6iteoyG5wiOacJTMR5rAtJMCB5T2OcBwxzB-nMuKRy34p31Gykl44OH4SmzLs0My6TgJ2e8fvX11ejRqSK6iB-Tqgew0Gxm_KfeS0NmR5LSz8L0f26eGCOmCofaLgh1fSW7oOHAOY0TL0wthJMjGwPAOZgYUgtyb8osaoMcgSBnMHpEVpbOmLNTcUlvbMJLOqR9FMKSQrxav2cXSPvYYCfiKQkXNgMt0ulPowZmJzzkBVmkryADJ8ekhpYsUp3K8i5UnEfu1wwiRRs_kkjWFwnz62FmpFuTxPSM2PwpSksGS0

@startuml

package "PSR-7" {
 interface Psr7\MessageInterface

 interface Psr7\RequestInterface extends Psr7\MessageInterface
 note left of Psr7\RequestInterface
 an outgoing request.
 end note

 interface Psr7\ServerRequestInterface extends Psr7\RequestInterface
 note left of Psr7\ServerRequestInterface
 an incoming request.
 end note
}

package "CI4" {
 interface MessageInterface
 interface RequestInterface
 class Message implements MessageInterface
 class Request extends Message implements MessageInterface, RequestInterface

 class IncomingRequest extends Request
 note top of IncomingRequest
 an incoming request for HTTP.
 end note

 class CLIRequest extends Request
 note top of CLIRequest
 an incoming request for CLI.
 end note

 class CURLRequest extends Request
 note top of CURLRequest
 an outgoing request.
 end note
}

@enduml

[paulbalandan]

Fixed in #6698