chaos: fix utf8mb3 and utf8mb4_0900_ai_ci for chaos test

[GMHDBJD]

What problem does this PR solve?

Issue Number: ref #4159

What is changed and how it works?

• create database with charset latin1
• use utf8mb4 instead of utf8, see use utf8mb4 instead of utf8 PingCAP-QE/go-sqlsmith#18

Release note

None

[codecov-commenter]

Codecov Report

Merging #6960 (a01fa93) into master (9398176) will increase coverage by 0.0337%.
The diff coverage is 58.4816%.

❗ Current head a01fa93 differs from pull request most recent head c88aa9a. Consider uploading reports for the commit c88aa9a to get more accurate results

Additional details and impacted files

Flag	Coverage Δ
cdc	67.2470% <57.8048%> (+0.0510%)	⬆️
dm	51.9098% <25.0000%> (-0.0382%)	⬇️
engine	62.3559% <60.4316%> (+0.0937%)	⬆️

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

@@               Coverage Diff                @@
##             master      #6960        +/-   ##
================================================
+ Coverage   59.8253%   59.8591%   +0.0337%     
================================================
  Files           791        790         -1     
  Lines         90221      90561       +340     
================================================
+ Hits          53975      54209       +234     
- Misses        31498      31592        +94     
- Partials       4748       4760        +12     

[GMHDBJD]

/hold

[GMHDBJD]

https://github.com/pingcap/tiflow/actions/runs/2997517629 chaos test passed. cc @lance6716 @D3Hunter @buchuitoudegou

[GMHDBJD]

/unhold

[ti-chi-bot]

[REVIEW NOTIFICATION]

This pull request has been approved by:

• D3Hunter
• lance6716

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[lance6716]

/merge

[ti-chi-bot]

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

Commit hash: bb64a8e

[GMHDBJD]

/merge

[lance6716]

/run-verify
/run-dm-integration-test

[ti-chi-bot]

@GMHDBJD: Your PR was out of date, I have automatically updated it for you.

At the same time I will also trigger all tests for you:

/run-all-tests

If the CI test fails, you just re-trigger the test that failed and the bot will merge the PR for you after the CI passes.

Instructions for interacting with me using PR comments are available here. If you have questions or suggestions related to my behavior, please file an issue against the ti-community-infra/tichi repository.

[lance6716]

/run-dm-integration-test