feat: support bytes as query value

[trim21]

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Summary

ref: https://github.com/encode/httpx/issues/3170

bytes as query string are supported by url spec but not httpx, this PR add support for bytes query value types.

it also fix a QueryParams mutable problem when using set/add

Checklist

• [X] I understand that this PR may be closed in case there was no previous discussion. (This doesn't apply to typos!)
• [x] I've added a test for each change that was introduced, and I tried as much as possible to make a single atomic change.
• [ ] I've updated the documentation accordingly.