Merge bitcoin/bitcoin#24378: refactor: make bind() and listen() mockable/testable

b2733ab6a8 net: add new method Sock::Listen() that wraps listen() (Vasil Dimov)
3ad7de225e net: add new method Sock::Bind() that wraps bind() (Vasil Dimov)

Pull request description:

  _This is a piece of #21878, chopped off to ease review._

  Add new methods `Sock::Bind()` and `Sock::Listen()` that wrap `bind()` and `listen()`.
  This will help to increase `Sock` usage and make more code mockable.

ACKs for top commit:
  pk-b2:
    ACK b2733ab6a8
  laanwj:
    Code review ACK b2733ab6a8

Tree-SHA512: c6e737606703e2106fe60cc000cfbbae3a7f43deadb25f70531e2cac0457e0b0581440279d14c76c492eb85c12af4adde52c30baf74542c41597e419817488e8

src/test/util/net.h

@@ -122,6 +122,10 @@ public:
 
     int Connect(const sockaddr*, socklen_t) const override { return 0; }
 
+    int Bind(const sockaddr*, socklen_t) const override { return 0; }
+
+    int Listen(int) const override { return 0; }
+
     std::unique_ptr<Sock> Accept(sockaddr* addr, socklen_t* addr_len) const override
     {
         if (addr != nullptr) {