etcd client leak when a table uses AUTO_ID_CACHE=1 and auto_increment

[D3Hunter]

Bug Report

Please answer these questions before submitting your issue. Thanks!

1. Minimal reproduce step (Required)

nowhere close this etcd client

tidb/meta/autoid/autoid.go

Line 588 in 1769f3a

etcdCli, err := clientv3.New(clientv3.Config{

2. What did you expect to see? (Required)

3. What did you see instead (Required)

4. What is your TiDB version? (Required)

this code is introduced in tidb version >= 6.4.0