actix-web: Add rustls 0.23 (#3363)

* Fix type confusion in some scenarios

When the feature for rustls 0.22 is enabled, and rustls 0.23 is also
present in a project, there suddently exist multiple paths for errors
when building middleware chains due to the use of two consecutive `?`
operators without specifying the intermediate error type.

This commit addresses the issue by removing the first `?`, so that the
first error type will always be known, and the second `?` always has a
well defined implementation.

* Add CHANGES entry about type confusion

* actix-http: add rustls 0.23 support

* actix-http: update ws example, tests for rustls 0.23

* actix-http: add rustls 0.23 to changelog

* Update comments to mention 0.23 instead of 0.22

* awc: add rustls 0.23 support

This also fixes certificate lookup when native-roots is enabled for rustls 0.22.

* awc: update changelog for rustls 0.23

* awc: Add base rustls-0_23 feature without roots to better enable custom config

* actix-test: add rustls-0.23

* actix-test: add rustls 0.23 to changelog

* awc: update changelog with rustls 0.23 tweaks

* actix-web: add rustls 0.23

* Add rustls-0_23 to CI

* Update tls_rustls.rs

* review nits

* review nits part 2

* fix doc test

---------

Co-authored-by: Rob Ede <robjtede@icloud.com>

awc/CHANGES.md

@@ -2,6 +2,9 @@
 
 ## Unreleased
 
+- Add `rustls-0_23`, `rustls-0_23-webpki-roots`, and `rustls-0_23-native-roots` crate features.
+- Add `awc::Connector::rustls_0_23()` constructor.
+- Fix `rustls-0_22-native-roots` root store lookup
 - Update `brotli` dependency to `6`.
 - Minimum supported Rust version (MSRV) is now 1.72.