Revert "pkgqueue_get_next: find(1) in the queue should not fail"

This reverts commit 11baebf.

The find(1) is racy. The callers handle the situation properly.

	find: unbalanced/run:qt6-quicktimeline-6.6.3: No such file or directory
	[00:07:25] Error: [92639] /usr/local/share/poudriere/bulk.sh:pkgqueue_get_next:12:pkgqueue_get_next: Failed to search queue

src/share/poudriere/include/pkgqueue.sh

@@ -78,8 +78,7 @@ pkgqueue_get_next() {
 	# May need to try multiple times due to races and queued-for-order jobs
 	while :; do
 		pkgq_dir="$(find ${POOL_BUCKET_DIRS:?} \
-		    -type d -depth 1 -empty -print -quit)" ||
-		    err "${EX_SOFTWARE}" "pkgqueue_get_next: Failed to search queue"
+		    -type d -depth 1 -empty -print -quit || :)"
 		# No more eligible work!
 		case "${pkgq_dir}" in
 		"")