gwakeuptest: Do not rely on alarm() to stop tests on timeout

We have meson nowadays, so tests are timing out by default and test timeout
may vary depending on the meson test parameters or test setups.

So don't hardcode it using alarm().

glib/tests/gwakeuptest.c

@@ -1,12 +1,5 @@
 #include <glib.h>
 #include <glib/gwakeup.h>
-#ifdef G_OS_UNIX
-#include <unistd.h>
-#endif
-
-#ifdef _WIN32
-static void alarm (int sec) { }
-#endif
 
 static gboolean
 check_signaled (GWakeup *wakeup)
@@ -32,9 +25,6 @@ test_semantics (void)
   GWakeup *wakeup;
   gint i;
 
-  /* prevent the test from deadlocking */
-  alarm (60);
-
   wakeup = g_wakeup_new ();
   g_assert (!check_signaled (wakeup));
 
@@ -66,9 +56,6 @@ test_semantics (void)
   g_assert (!check_signaled (wakeup));
 
   g_wakeup_free (wakeup);
-
-  /* cancel the alarm */
-  alarm (0);
 }
 
 struct token
@@ -213,9 +200,6 @@ test_threaded (void)
 {
   gint i;
 
-  /* make sure we don't block forever */
-  alarm (60);
-
   /* simple mainloop test based on GWakeup.
    *
    * create a bunch of contexts and a thread to 'run' each one.  create
@@ -252,9 +236,6 @@ test_threaded (void)
     }
 
   g_wakeup_free (last_token_wakeup);
-
-  /* cancel alarm */
-  alarm (0);
 }
 
 int