ticdc/server: output the cdc server cmd error to stderr (#3520)

[ti-chi-bot]

This is an automated cherry-pick of #3520

What problem does this PR solve?

issue 3133

What is changed and how it works?

Make stderr as cdc server's cmd error destination. By this way, users can get the detailed messages from cdc_stderr.log.

Check List

Tests

• Unit test
• Integration test

Release note

None

[ti-chi-bot]

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[codecov-commenter]

Codecov Report

❗ No coverage uploaded for pull request base (release-5.1@d201603). Click here to learn what that means.
The diff coverage is n/a.

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[overvenus]

/merge

[ti-chi-bot]

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

Commit hash: c79c0eb