Minor edit to intro paragraph

[ceohockey60]

Minor edit to intro paragraph, so it's less repetitive.

What problem does this PR solve?

What is changed and how it works?

Check List

Tests

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

Code changes

• Has exported function/method change
• Has exported variable/fields change
• Has interface methods change
• Has persistent data change

Side effects

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

Related changes

• Need to cherry-pick to the release branch
• Need to update the documentation
• Need to update the tidb-ansible repository
• Need to be included in the release note

[ceohockey60]

@morgo PTAL. thank you.

[morgo]

LGTM

[morgo]

@kolbe PTAL

[kolbe]

LGTM

[codecov]

Codecov Report

❗ No coverage uploaded for pull request base (master@8e0cfc2). Click here to learn what that means.
The diff coverage is n/a.

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##             master      #9944   +/-   ##
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  Coverage          ?   77.5531%           
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  Files             ?        404           
  Lines             ?      81722           
  Branches          ?          0           
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  Hits              ?      63378           
  Misses            ?      13642           
  Partials          ?       4702

[morgo]

/run-all-tests