Fix: Bucket resource leak when cleanup

Fix: Bucket resource leak when cleanup

In the function of nuke_prefixed_buckets, if some err is thrown when deleting buckets, the left buckets remain uncleaned.
It is kind of resoruce leak on some charged platform. We have to clear them manually.

I know the original code is meant to give the user some hint by rasing error. But the resource leak of left buckets is a little annoying.

This PR would skip the problem point and continue the teardown process. The last client error would be saved and re-raised after the loop completes.

Signed-off-by: Pei <huangp0600@126.com>
Signed-off-by: Pei <phuang1@dev-new-3-3854897.slc07.dev.ebayc3.com>