disttask: fix scope can't set different value (#52627)

[ti-chi-bot]

This is an automated cherry-pick of #52627

What problem does this PR solve?

Issue Number: close #52441

Problem Summary:

What changed and how does it work?

1. Make tidb_service_scope can be set to different values.
2. add target scope for each tasks

Check List

Tests

• Unit test
• Integration test
• Manual test (add detailed scripts or steps below)
• No need to test

  • I checked and no code files have been changed.

Side effects

• Performance regression: Consumes more CPU
• Performance regression: Consumes more Memory
• Breaking backward compatibility

Documentation

• Affects user behaviors
• Contains syntax changes
• Contains variable changes
• Contains experimental features
• Changes MySQL compatibility

Release note

Please refer to Release Notes Language Style Guide to write a quality release note.

None

[Benjamin2037]

LGTM

[ti-chi-bot]

[LGTM Timeline notifier]

Timeline:

• 2024-04-26 07:52:33.322103101 +0000 UTC m=+333110.062006012: ☑️ agreed by Benjamin2037.
• 2024-04-26 07:55:54.920074676 +0000 UTC m=+333311.659977590: ☑️ agreed by ywqzzy.

[codecov]

Codecov Report

Attention: Patch coverage is 96.62921% with 3 lines in your changes are missing coverage. Please review.

❗ No coverage uploaded for pull request base (release-8.1@e34e65f). Click here to learn what that means.

Additional details and impacted files

@@               Coverage Diff                @@
##             release-8.1     #52909   +/-   ##
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  Coverage               ?   71.6256%           
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Flag	Coverage Δ
unit	71.6256% <96.6292%> (?)

Flags with carried forward coverage won't be shown. Click here to find out more.

Components	Coverage Δ
dumpling	53.9957% <0.0000%> (?)
parser	∅ <0.0000%> (?)
br	40.9483% <0.0000%> (?)

[easonn7]

/approve

[ti-chi-bot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: Benjamin2037, D3Hunter, easonn7, Leavrth, ywqzzy

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

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Needs approval from an approver in each of these files:

• OWNERS [Benjamin2037,D3Hunter,Leavrth,ywqzzy]
• br/OWNERS [Leavrth]
• pkg/ddl/OWNERS [Benjamin2037,ywqzzy]
• pkg/disttask/OWNERS [Benjamin2037,D3Hunter,ywqzzy]
• pkg/executor/importer/OWNERS [D3Hunter]
• pkg/parser/OWNERS [D3Hunter]
• pkg/session/OWNERS [easonn7]
• pkg/sessionctx/variable/OWNERS [easonn7]

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[ywqzzy]

/retest