fix: remove unnecessary filter_map usages

[wowinter13]

fixes https://github.com/rust-lang/rust-clippy/issues/12556

(Fixed version of https://github.com/rust-lang/rust-clippy/pull/12766)

changelog: [unnecessary_filter_map]: filter map improvements

[rustbot]

Thanks for the pull request, and welcome! The Rust team is excited to review your changes, and you should hear from @llogiq (or someone else) some time within the next two weeks.

Please see the contribution instructions for more information. Namely, in order to ensure the minimum review times lag, PR authors and assigned reviewers should ensure that the review label (S-waiting-on-review and S-waiting-on-author) stays updated, invoking these commands when appropriate:

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[wowinter13]

@rustbot ready

[llogiq]

Thank you! @bors r+

[bors]

:pushpin: Commit ad002ea99f5e5ca6e47a9550964bf0a882083e5b has been approved by llogiq

It is now in the queue for this repository.

[bors]

:hourglass: Testing commit ad002ea99f5e5ca6e47a9550964bf0a882083e5b with merge 73bad368f2277511659969f4dc40dff1a6db2df8...

[bors]

:sunny: Test successful - checks-action_dev_test, checks-action_remark_test, checks-action_test Approved by: llogiq Pushing 73bad368f2277511659969f4dc40dff1a6db2df8 to master...