Existing changefeeds show lag spikes after deleting many changefeeds in a short time

[lidezhu]

What did you do?

Multiple changefeeds are deleted within a short period.

cdc version: v8.5.7-release.1

What did you expect to see?

Deleting changefeeds should not cause noticeable checkpoint/resolved lag spikes on other existing running changefeeds.

What did you see instead?

Existing running changefeeds may show a temporary lag spike.

Versions of the cluster

Upstream TiDB cluster version (execute SELECT tidb_version(); in a MySQL client):

(paste TiDB cluster version here)

Upstream TiKV version (execute tikv-server --version):

(paste TiKV version here)

TiCDC version (execute cdc version):

(paste TiCDC version here)