Include <cstdint> when compiling TinyWebSockets.

[developer79433]

Fixes:

In file included from external/TinyWebsockets/tiny_websockets_lib/include/tiny_websockets/network/linux/linux_tcp_client.hpp:6,
                 from external/TinyWebsockets/tiny_websockets_lib/include/tiny_websockets/internals/ws_common.hpp:37,
                 from external/TinyWebsockets/tiny_websockets_lib/include/tiny_websockets/internals/wscrypto/crypto.hpp:3,
                 from external/TinyWebsockets/tiny_websockets_lib/src/crypto.cpp:1:
external/TinyWebsockets/tiny_websockets_lib/include/tiny_websockets/network/tcp_client.hpp:11:29: error: ‘uint8_t’ does not name a type
   11 |     virtual void send(const uint8_t* data, const uint32_t len) = 0;
      |                             ^~~~~~~
external/TinyWebsockets/tiny_websockets_lib/include/tiny_websockets/network/tcp_client.hpp:5:1: note: ‘uint8_t’ is defined in header ‘<cstdint>’; this is probably fixable by adding ‘#include <cstdint>’
    4 | #include <tiny_websockets/network/tcp_socket.hpp>
  +++ |+#include <cstdint>
    5 |