Build failing if `dns-resolver` feature is disabled on 3.2.0

[noaione]

Versions/Environment

1. What version of Rust are you using? 1.84.0
2. What operating system are you using? Windows 11
3. What versions of the driver and its dependencies are you using? 3.2.0 (bson 2.13.0)
4. What version of MongoDB are you using? Not applicable
5. What is your MongoDB topology? Not applicable

Describe the bug

Previously, I've build my project with mongodb driver with the following features list:

mongodb = { version = "3.2.0", default-features = false, features = ["compat-3-0-0", "rustls-tls"] }

Starting from v3.2.0, my build is failing because some part are not guarded properly if dns-resolver is disabled.

Error log: https://gist.github.com/noaione/f5b02d0e2129b0fe7ed67f3bc7d66519

To Reproduce

1. Create a new project
2. Add mongodb as dependencies with default features disabled with compat-3-0-0 and rustls-tls as feature
3. Build the project
4. It fails to build (see error log above)

[isabelatkinson]

Hey @noaione, thanks for reporting this! I'm taking a look and will get back to you with a fix.

[isabelatkinson]

@noaione #1292 fixes this. I'll talk to the team about getting out patch release next week. Thanks again for the report!

[noaione]

Thanks! I've tried building using your branch and it seems like everything build properly now.