TiDB lighitng failed for the error of requested pd is not leader of cluster

## Bug Report

Please answer these questions before submitting your issue. Thanks!

### 1. Minimal reproduce step (Required)

/tidb-lightning \"-pd-urls\" \"tc-pd.e2e-htap-encryption-tps-1302571-1-900:2379\" \"-tidb-host\" \"tc-tidb.e2e-htap-encryption-tps-1302571-1-900\" \"-tidb-port\" \"4000\" \"-tidb-user\" \"root\" \"-tidb-password\" \"\" \"-backend\" \"local\" \"-sorted-kv-dir\" \"/tmp/sorted-kv-dir\" \"-d\" \"s3://nfs/tiflash/csv-tpcc-100?access-key=minioadmin&secret-access-key=minioadmin&endpoint=http%3a%2f%2fminio.pingcap.net%3a9000&force-path-style=true\" \"-c\" \"/lightning.yaml\""

### 2. What did you expect to see? (Required)
success
### 3. What did you see instead (Required)
```
[2022/10/30 18:38:24.213 +00:00] [ERROR] [restore.go:1528] ["restore all tables data failed"] [takeTime=11m17.100654126s] [error="fetch tso from pd failed: rpc error: code = Unknown desc = [PD:tso:ErrGenerateTimestamp]generate timestamp failed, requested pd is not leader of cluster"]
[2022/10/30 18:38:24.213 +00:00] [INFO] [restore.go:1171] ["everything imported, stopping periodic actions"]
[2022/10/30 18:38:24.213 +00:00] [ERROR] [restore.go:466] ["run failed"] [step=4] [error="fetch tso from pd failed: rpc error: code = Unknown desc = [PD:tso:ErrGenerateTimestamp]generate timestamp failed, requested pd is not leader of cluster"]
[2022/10/30 18:38:24.213 +00:00] [ERROR] [restore.go:476] ["the whole procedure failed"] [takeTime=11m18.462109893s] [error="fetch tso from pd failed: rpc error: code = Unknown desc = [PD:tso:ErrGenerateTimestamp]generate timestamp failed, requested pd is not leader of cluster"]
[2022/10/30 18:38:24.321 +00:00] [INFO] [checksum.go:459] ["service safe point keeper exited"]
[2022/10/30 18:38:24.321 +00:00] [ERROR] [main.go:103] ["tidb lightning encountered error stack info"] [error="fetch tso from pd failed: rpc error: code = Unknown desc = [PD:tso:ErrGenerateTimestamp]generate timestamp failed, requested pd is not leader of cluster"] [errorVerbose="rpc error: code = Unknown desc = [PD:tso:ErrGenerateTimestamp]generate timestamp failed, requested pd is not leader of cluster\ngithub.com/tikv/pd/client.(*client).processTSORequests\n\t/go/pkg/mod/github.com/tikv/pd/client@v0.0.0-20221010134149-d50e5fe43f14/client.go:1092\ngithub.com/tikv/pd/client.(*client).handleDispatcher\n\t/go/pkg/mod/github.com/tikv/pd/client@v0.0.0-20221010134149-d50e5fe43f14/client.go:842\nruntime.goexit\n\t/usr/local/go/src/runtime/asm_amd64.s:1594\ngithub.com/tikv/pd/client.(*tsoRequest).Wait\n\t/go/pkg/mod/github.com/tikv/pd/client@v0.0.0-20221010134149-d50e5fe43f14/client.go:1308\ngithub.com/tikv/pd/client.(*client).GetTS\n\t/go/pkg/mod/github.com/tikv/pd/client@v0.0.0-20221010134149-d50e5fe43f14/client.go:1328\ngithub.com/pingcap/tidb/br/pkg/lightning/restore.(*tikvChecksumManager).Checksum\n\t/home/jenkins/agent/workspace/build-common/go/src/github.com/pingcap/br/br/pkg/lightning/restore/checksum.go:315\ngithub.com/pingcap/tidb/br/pkg/lightning/restore.DoChecksum\n\t/home/jenkins/agent/workspace/build-common/go/src/github.com/pingcap/br/br/pkg/lightning/restore/checksum.go:161\ngithub.com/pingcap/tidb/br/pkg/lightning/restore.(*TableRestore).postProcess\n\t/home/jenkins/agent/workspace/build-common/go/src/github.com/pingcap/br/br/pkg/lightning/restore/table_restore.go:800\ngithub.com/pingcap/tidb/br/pkg/lightning/restore.(*Controller).restoreTables.func7.1\n\t/home/jenkins/agent/workspace/build-common/go/src/github.com/pingcap/br/br/pkg/lightning/restore/restore.go:1652\nruntime.goexit\n\t/usr/local/go/src/runtime/asm_amd64.s:1594\nfetch tso from pd failed"]
```
### 4. What is your TiDB version? (Required)

master