The device remove test was sporadically failing, because we hadn't
finished dropping btree sector counts for the device when
bch2_replicas_gc2() was called - mainly due to in flight journal writes.
We don't yet have a good mechanism for flushing the counts that
correspend to open journal entries yet.
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com> Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>