update(index): update _index.md link to relative link

[shhdgit]

First-time contributors' checklist

• [x] I've signed Contributor License Agreement that's required for repo owners to accept my contribution.

What is changed, added or deleted? (Required)

Related issue: https://github.com/pingcap/docs/issues/19656

Hold until https://github.com/pingcap/website-docs/pull/569 is merged.

Which TiDB version(s) do your changes apply to? (Required)

Tips for choosing the affected version(s):

By default, CHOOSE MASTER ONLY so your changes will be applied to the next TiDB major or minor releases. If your PR involves a product feature behavior change or a compatibility change, CHOOSE THE AFFECTED RELEASE BRANCH(ES) AND MASTER.

For details, see tips for choosing the affected versions.

• [x] master (the latest development version)
• [x] v8.5 (TiDB 8.5 versions)
• [ ] v8.4 (TiDB 8.4 versions)
• [ ] v8.3 (TiDB 8.3 versions)
• [ ] v8.2 (TiDB 8.2 versions)
• [x] v8.1 (TiDB 8.1 versions)
• [ ] v7.5 (TiDB 7.5 versions)
• [ ] v7.1 (TiDB 7.1 versions)
• [ ] v6.5 (TiDB 6.5 versions)
• [ ] v6.1 (TiDB 6.1 versions)
• [ ] v5.4 (TiDB 5.4 versions)
• [ ] v5.3 (TiDB 5.3 versions)

What is the related PR or file link(s)?

• This PR is translated from:
• Other reference link(s):

Do your changes match any of the following descriptions?

• [ ] Delete files
• [ ] Change aliases
• [ ] Need modification after applied to another branch
• [ ] Might cause conflicts after applied to another branch

[ti-chi-bot[bot]]

[LGTM Timeline notifier]

Timeline:

• 2024-12-20 10:22:11.249618683 +0000 UTC m=+1211521.338421222: :ballot_box_with_check: agreed by qiancai.

[ti-chi-bot[bot]]

@Yuiham: adding LGTM is restricted to approvers and reviewers in OWNERS files.

In response to this:

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 kubernetes-sigs/prow repository.

[qiancai]

/approve

[ti-chi-bot[bot]]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: qiancai

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~~ [qiancai]

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

[ti-chi-bot[bot]]

@qiancai: You cannot manually add or delete the cherry pick approval state labels, only I and the tursted members have permission to do so. You can approve it in internal platform.

In response to removing label named approved.

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.

[ti-chi-bot[bot]]

@shhdgit: The following test failed, say /retest to rerun all failed tests or /retest-required to rerun all mandatory failed tests:

Test name	Commit	Details	Required	Rerun command
pull-verify	12724247d4bb115cae7e1cd3146fa611b554ee51	link	true	/test pull-verify

Full PR test history. Your PR dashboard.

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 kubernetes-sigs/prow repository. I understand the commands that are listed here.