[MNT] Add tests for BA weight parameters

[chrisholder]

Reference Issues/PRs

This PR adds missing tests from PR #1563

What does this implement/fix? Explain your changes.

The BA weights parameter was missing tests so this PR adds those tests.

Does your contribution introduce a new dependency? If yes, which one?

No

Any other comments?

No

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I have added the following labels to this PR based on the title: [ $\color{#EC843A}{\textsf{maintenance}}$ ].
I have added the following labels to this PR based on the changes made: [ $\color{#4011F3}{\textsf{clustering}}$ ]. Feel free to change these if they do not properly represent the PR.

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[hadifawaz1999]

LGTM!