develop: update TiDB Cloud Import page and Connect page

[Oreoxmt]

What is changed, added or deleted? (Required)

• update connection page for TiDB Dedicated clusters
• rename Endpoint Type to Connection Type for TiDB Serverless
• update TiDB Cloud Import page

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)
• v8.4 (TiDB 8.4 versions)
• v8.3 (TiDB 8.3 versions)
• v8.2 (TiDB 8.2 versions)
• 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: develop: update TiDB Cloud Import page docs#18780, cloud: rename Endpoint Type to Connection Type for TiDB Serverless docs#18756, develop: update connection page for TiDB Dedicated clusters docs#18718
• 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

[lilin90]

/lgtm

[ti-chi-bot]

[LGTM Timeline notifier]

Timeline:

• 2024-09-10 07:53:18.597307452 +0000 UTC m=+342868.337731391: ☑️ agreed by lilin90.

[Oreoxmt]

/approve

[ti-chi-bot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: Oreoxmt

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• develop/OWNERS [Oreoxmt]

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[ti-chi-bot]

In response to a cherrypick label: new pull request created to branch release-7.1: #18593.

[ti-chi-bot]

In response to a cherrypick label: new pull request created to branch release-7.5: #18594.

[ti-chi-bot]

In response to a cherrypick label: new pull request created to branch release-8.1: #18595.

[ti-chi-bot]

In response to a cherrypick label: new pull request created to branch release-8.2: #18596.

[ti-chi-bot]

In response to a cherrypick label: new pull request created to branch release-8.3: #18597.