tests: Remove various bits of overly-verbose test output

None of these messages are particularly helpful, but they increase the
overall test log output size, which has to be stored by the CI for every
test run.

With these messages removed, the size of a full test log is reduced from
6.5MB to 1.8MB for me.

Signed-off-by: Philip Withnall <pwithnall@endlessos.org>

gobject/tests/objects-refcount1.c

@@ -103,7 +103,6 @@ run_thread (GTest * test)
   while (!g_atomic_int_get (&stopping)) {
     my_test_do_refcount (test);
     if ((i++ % 10000) == 0) {
-        g_test_message (".");
         g_thread_yield (); /* force context switch */
     }
   }

gobject/tests/properties-refcount3.c

@@ -144,7 +144,6 @@ run_thread (GTest * test)
     my_test_do_property (test);
     if ((i++ % 10000) == 0)
       {
-        g_test_message (".%c", 'a' + test->id);
         g_thread_yield(); /* force context switch */
       }
   }

gobject/tests/signals-refcount.c

@@ -236,7 +236,6 @@ run_thread (GTest * test)
     if (TESTNUM == 4)
       my_test_do_signal3 (test);
     if ((i++ % 10000) == 0) {
-        g_test_message (".");
         g_thread_yield (); /* force context switch */
     }
   }
@@ -250,7 +249,8 @@ notify (GObject *object, GParamSpec *spec, gpointer user_data)
   gint value;
 
   g_object_get (object, "test-prop", &value, NULL);
-  g_test_message ("+ %d", value);
+  if (TESTNUM != 3)
+    g_assert_cmpint (value, ==, 0);
 }
 
 static void