config: increase the default lease (#9173)

[ti-chi-bot]

This is an automated cherry-pick of #9173

What problem does this PR solve?

Issue Number: Close #9156.

What is changed and how does it work?

According to the maintainer's comment in etcd-io/etcd#18091 (reply in thread). It is not recommended to use a short lease, which is less than 3s. I think we also need to change the default lease.

Check List

Tests

• Unit test

Release note

None.

[ti-chi-bot]

[APPROVALNOTIFIER] This PR is NOT APPROVED

This pull-request has been approved by: bufferflies, lhy1024
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[ti-chi-bot]

[LGTM Timeline notifier]

Timeline:

• 2025-07-10 01:33:51.434694285 +0000 UTC m=+2136284.157873267: ☑️ agreed by bufferflies.
• 2025-07-10 03:00:09.613351903 +0000 UTC m=+2141462.336530885: ☑️ agreed by lhy1024.

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