client: Fix an issue where non-IP proxy URLs didn’t resolve correctly (#32664)

If the proxy URL is in the form of `example.com` instead of a raw IP
address, and `example.com` isn't a well-known domain, then the default
URL resolution can fail.

The test setup:

A Linux machine runs a CoreDNS server with a custom entry: `10.254.7.38
example.com`. On a Windows machine, if the proxy URL is set to
`example.com`, the resolved address does **not** end up being
`10.254.7.38`.

Using `hickory_resolver` for more advanced DNS resolution fixes this
issue.


Release Notes:

- Fixed proxy URL resolution when using custom DNS entries.

Cargo.toml

@@ -524,6 +524,7 @@ reqwest = { git = "https://github.com/zed-industries/reqwest.git", rev = "951c77
     "rustls-tls-native-roots",
     "socks",
     "stream",
+    "hickory-dns",
 ] }
 rsa = "0.9.6"
 runtimelib = {  git = "https://github.com/ConradIrwin/runtimed", rev = "7130c804216b6914355d15d0b91ea91f6babd734", default-features = false, features = [