fix: EC volume deletion issues
Fixes#7489
1. Skip cookie check for EC volume deletion when SkipCookieCheck is set
When batch deleting files from EC volumes with SkipCookieCheck=true
(e.g., orphan file cleanup), the cookie is not available. The deletion
was failing with 'unexpected cookie 0' because DeleteEcShardNeedle
always validated the cookie.
2. Optimize doDeleteNeedleFromAtLeastOneRemoteEcShards to return early
Return immediately when a deletion succeeds, instead of continuing
to try all parity shards unnecessarily.
3. Remove useless log message that always logged nil error
The log at V(1) was logging err after checking it was nil.
Regression introduced in commit 7bdae5172 (Jan 3, 2023) when EC batch
delete support was added.
