releases: add tidb 5.1.4 release notes

[ti-srebot]

What is changed, added or deleted? (Required)

Release notes 5.1.4

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 (in Chinese).

• master (the latest development version)
• v5.4 (TiDB 5.4 versions)
• v5.3 (TiDB 5.3 versions)
• v5.2 (TiDB 5.2 versions)
• v5.1 (TiDB 5.1 versions)
• v5.0 (TiDB 5.0 versions)
• v4.0 (TiDB 4.0 versions)
• v3.1 (TiDB 3.1 versions)
• v3.0 (TiDB 3.0 versions)
• v2.1 (TiDB 2.1 versions)

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

• docs-cn PR: Release notes 5.1.4 docs-cn#8336
• 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

[hfxsd]

/merge

[ti-chi-bot]

This pull request has been accepted and is ready to merge.

Commit hash: f4e3f51

[ti-chi-bot]

In response to a cherrypick label: new pull request created: #7666.

[ti-chi-bot]

In response to a cherrypick label: new pull request created: #7667.

[ti-chi-bot]

In response to a cherrypick label: new pull request created: #7668.

[ti-chi-bot]

In response to a cherrypick label: new pull request created: #7669.