config: completely remove the deprecated field from the PD server config (#8981)

[ti-chi-bot]

This is an automated cherry-pick of #8981

What problem does this PR solve?

Issue Number: Close #8980

What is changed and how does it work?

server/config: completely remove the deprecated field from the PD server config

Check List

Tests

• Unit test
• Integration test
• Manual test (add detailed scripts or steps below)

From 7.1.1 to master:

master restart twice:

Code changes

• Has the configuration change
• Has HTTP API interfaces changed (Don't forget to add the declarative for the new API)
• Has persistent data change

Side effects

• Possible performance regression
• Increased code complexity
• Breaking backward compatibility

Related changes

• PR to update pingcap/docs/pingcap/docs-cn:
• PR to update pingcap/tiup:
• Need to cherry-pick to the release branch

Release note

None.

[ti-chi-bot]

@nolouch This PR has conflicts, I have hold it.
Please resolve them or ask others to resolve them, then comment /unhold to remove the hold label.

[rleungx]

/unhold

[ti-chi-bot]

[LGTM Timeline notifier]

Timeline:

• 2025-02-12 06:58:40.042203311 +0000 UTC m=+426162.438425373: ☑️ agreed by rleungx.
• 2025-02-12 06:59:55.325527279 +0000 UTC m=+426237.721749337: ☑️ agreed by lhy1024.

[ti-chi-bot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: lhy1024, niubell, rleungx

The full list of commands accepted by this bot can be found here.

The pull request process is described here

Needs approval from an approver in each of these files:

• OWNERS [lhy1024,rleungx]
• server/config/OWNERS [niubell]

Approvers can indicate their approval by writing /approve in a comment
Approvers can cancel approval by writing /approve cancel in a comment

[rleungx]

/retest

[ti-chi-bot]

@ti-chi-bot: Your PR was out of date, I have automatically updated it for you.

If the CI test fails, you just re-trigger the test that failed and the bot will merge the PR for you after the CI passes.

Instructions for interacting with me using PR comments are available here. If you have questions or suggestions related to my behavior, please file an issue against the ti-community-infra/tichi repository.

[rleungx]

/retest