Fixing `aligned` equations in impl content since they don't render properly with needextract

[zachmprince]

What is the change?

Math with align triggers like & does not render properly within impl content when using .. needextract for the PDF build. It does render properly within the API docs where they are placed, so be wary of future false positives.

Why is the change being made?

Ongoing SQA effort

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Checklist

• [ ] This PR has only one purpose or idea.
• [ ] Tests have been added/updated to verify that the new/changed code works.

• [ ] The code style follows good practices.
• [ ] The commit message(s) follow good practices.

• [ ] The release notes (location doc/release/0.X.rst) are up-to-date with any important changes.
• [ ] The documentation is still up-to-date in the doc folder.
• [ ] If any requirements were affected, mention it in the release notes.
• [ ] The dependencies are still up-to-date in pyproject.toml.

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