meson: Mark 1bit-emufutex test as slow

Emulated futexes are slower than real ones; if they were not, there
would be no point in using the real futexes. On some machines they
are sufficiently slow to cause test timeouts.

Signed-off-by: Simon McVittie <smcv@collabora.com>

glib/tests/meson.build

@@ -118,6 +118,7 @@ glib_tests = {
     'source' : '1bit-mutex.c',
     'c_args' : ['-DTEST_EMULATED_FUTEX'],
     'install' : false,
+    'suite' : ['slow'],
   },
   '642026' : {
     'suite' : ['slow'],