rename a shadowed test and re-enable F811 to catch future cases (#8139)

[alexmac]

(cherry picked from commit 3c0f1eb)

What do these changes do?

Are there changes in behavior for the user?

Is it a substantial burden for the maintainers to support this?

Related issue number

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[alexmac]

@Dreamsorcerer - here's one of the backports

[Dreamsorcerer]

@alexmac Looks like there's another shadowed test that'll need to be sorted in the backports.