fix: safe async parsing of connection strings

[mcasimir]

Description

Internal use of async/await and promises in Connection.from to simplify the code and properly deal with the asynchronous parsing in case of errors.

NOTE: we are also dropping the "normalisation" of the scheme (adding the scheme if not present). Since the url scheme is validated in compass-connect that feature is never used, also not behaving properly:

http://my-host --> mongodb://http://my-host

bad-protocol://somehost?#mongodb+srv:// --> bad-protocol://somehost?#mongodb+srv://

To be precise this should probably be a new major version.

Checklist

• [x] New tests and/or benchmarks are included
• [ ] Documentation is changed or added

Motivation and Context

• [x] Bugfix
• [ ] New feature
• [ ] Dependency update
• [ ] Misc

Open Questions

Dependents

Types of changes

• [ ] Backport Needed
• [ ] Patch (non-breaking change which fixes an issue)
• [ ] Minor (non-breaking change which adds functionality)
• [x] Major (fix or feature that would cause existing functionality to change)