Fix regression on Socket#connect timeout type restriction (#14755)

The `timeout` parameter of `system_connect` has an implict type restriction of `Time::Span?` and we need to convert numeric arguments. This fixes a regression introduced in #14643.

Author: straight-shoota

src/socket.cr

@@ -110,6 +110,7 @@ class Socket < IO
   # Tries to connect to a remote address. Yields an `IO::TimeoutError` or an
   # `Socket::ConnectError` error if the connection failed.
   def connect(addr, timeout = nil, &)
+    timeout = timeout.seconds unless timeout.is_a?(::Time::Span?)
     result = system_connect(addr, timeout)
     yield result if result.is_a?(Exception)
   end