Cleanup

[jplatte]

Commit descriptions should explain all changes :)

Fixes #115.

[jplatte]

EDIT: Now I can't find the failure I'm talking about below in CI logs, but a different one. Looks like the suggested MSRV of 1.51 doesn't work either because axum currently relies on the IntoIterator implementation for arrays added in Rust 1.53. Restoring compatibility with 1.51 might be as easy as changing the affected parts of the code to use array::IntoIter explicitly (stabilized in 1.51). I'll leave that up to somebody else though.

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This now removes one check from CI (second-to-last commit) but should be better than the status quo (due to #115).

This was necessary because cargo clippy on 1.51 failed because it didn't recognize msrv in .clippy.toml (of a dependency, hence removing axum's clippy config would not change anything).

[davidpdrsn]

create_url_params is only called in tests. So changing the call sites to use a slice is fine.

Thanks for doing this by the way! Gonna review it over the next few days.

[davidpdrsn]

I'm gonna merge this and fix CI on main. Would like to have this in when I start merging some of the many open PRs.