feat: add getter for scheme type

[d3lm]

This PR addresses #51 and adds a new getter to retrieve the schema type.

Todo

• [x] https://github.com/ada-url/ada/pull/503
• [x] https://github.com/ada-url/rust/pull/53
• [x] https://github.com/ada-url/rust/pull/54

[anonrig]

I recommend waiting for the function name change to merge this pull request.

[d3lm]

Yes, agreed. Updated the function name to scheme.

[d3lm]

PR updated to latest main.

[anonrig]

Thank you for your contribution @d3lm. Appreciate it!

[d3lm]

Thank you for the quick response times and reviewing all those PRs as well as cutting new releases that quickly 🙏