Fix default Alluxio writetype config (#3262)

[cheyang]

Ⅰ. Describe what this PR does

Ⅱ. Does this pull request fix one issue?

fixes #XXXX

Ⅲ. List the added test cases (unit test/integration test) if any, please explain if no tests are needed.

Ⅳ. Describe how to verify it

Ⅴ. Special notes for reviews

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[sonarqubecloud]

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