tests: reorder SIGWINCH to be after sleep

It looks like in a recent run:
https://github.com/qtile/qtile/actions/runs/8321862376/job/22786549176
which had my previous patch we didn't get the stack traces. Presumably
that's because we sent SIGWINCH and then immediately sent SIGKILL. I meant
to put this sleep *after* SIGWINCH to give python time to walk its stack,
but put it before. derp.

Signed-off-by: Tycho Andersen <tycho@tycho.pizza>

test/helpers.py

@@ -230,8 +230,8 @@ def terminate(self):
             if self.proc.is_alive():
                 # uh oh, we're hung somewhere. give it another second to print
                 # some stack traces
-                self.proc.join(1)
                 os.kill(self.proc.pid, signal.SIGWINCH)
+                self.proc.join(1)
                 print("Killing qtile forcefully", file=sys.stderr)
                 # desperate times... this probably messes with multiprocessing...
                 try: