Stop breaking TestUtil.cpp on Windows, dangit! (#11529)

* Stop breaking TestUtil.cpp on Windows, dangit!

* Update test/TestUtil.cpp

Co-authored-by: coderabbitai[bot] <136622811+coderabbitai[bot]@users.noreply.github.com>

---------

Co-authored-by: coderabbitai[bot] <136622811+coderabbitai[bot]@users.noreply.github.com>

test/TestUtil.cpp

@@ -40,6 +40,11 @@
 //
 // Listening sockets only: an outbound connection is a different (and louder) problem, and gethostby*
 // opens transient sockets that would make an any-socket check flap.
+// Linux-only: this check reads /proc; MinGW-w64 has no readlink() for fd links.
+// Linux CI covers the check; native Windows uses a no-op.
+#ifdef _WIN32
+static void assertNoListeningSockets() {}
+#else
 static void assertNoListeningSockets()
 {
     // Socket fds appear as "socket:[inode]"; a listening TCP row in /proc/self/net carries st 0A.
@@ -102,6 +107,7 @@ static void assertNoListeningSockets()
     exit(EXIT_FAILURE);
 }
 #endif
+#endif
 
 #if ARCH_PORTDUINO
 static bool environmentBaselined = false;