[hotfix][docs] Remove redundant import

[t0t07]

What is the purpose of the change

Remove redundant import from code.

Verifying this change

This change is a trivial rework / code cleanup without any test coverage.

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Automated Checks

Last check on commit b1c186c (Fri May 28 11:06:08 UTC 2021)

Warnings:

• No documentation files were touched! Remember to keep the Flink docs up to date!

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Review Progress

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• ❓ 5. Overall code [quality] is good.

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CI report:

• b1c186c Azure: SUCCESS

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