Added custom hashers support for HashSet and HashMap.

[s3rius]

Hello. The library is super great, but I noticed one problem. Custom hashers are not supported.

I introduced some new generics that allow you to serialize HashMaps and HashSets with custom hashers.

I wanted to speedup my code and have chosen ahash as custom hasher for my hashmaps. But found out that I need to convert hashmap back to default hasher in order to serialize it to valueslist.

Pre-review checklist

• I have split my patch into logically separate commits.
• All commit messages clearly explain what they change and why.
• I added relevant tests for new features and bug fixes.
• All commits compile, pass static checks and pass test.
• PR description sums up the changes and reasons why they should be introduced.
• I have provided docstrings for the public items that I want to introduce.
• I have adjusted the documentation in ./docs/source/.
• I added appropriate Fixes: annotations to PR description.

[piodul]

The min_rust check failed due to one of our indirect dependencies bumping up its MSRV. We'll fix that soon.

[piodul]

Thanks for the contribution.

It looks like you also need to modify the impl on line cql_to_rust.rs:203 so that deserialization of hashmaps with custom hashers is also possible.

Apart from that, two more nitpicks but LGTM otherwise.

[piodul]

The issue with failing min_rust check was fixed in #810. Rebase on main will be needed.

[piodul]

The test if_lwt_optimisation_mark_offered_then_negotiatied_and_lwt_routed_optimally failed twice and only succeeded now in the third run. It's not related to the PR at all so I'll merge, but I'll open an issue about this test being flaky.

[s3rius]

Thank you very much. Have a nice day.