community/gnome-clocks: fix waked patch

previous attempt forgot to guard WakedUtils.remove_timer behind if (!active), so it unconditionally removed the wakealarm.

since the patch looks a bit different from @psykose 's, here's what i did.

# inspect gnome-clocks commit log: git log --patch --reverse 43.0..44.0 -- 'src/*alarm*'
git am 0001...patch  # the old one from aports
# fix conflicts and massage the result into new code

I verified the patch on my pinephone (postmarketos-edge) with gnome-clocks built with this patch.