Add support for rustls-platform-verifier

[manifest]

Does your PR solve an issue?

fixes #4044

Is this a breaking change?

No.

This PR

• Adds optional dependency on rustls-platform-verifier.
• Adds new feature flags tls-rustls-aws-lc-rs-platform-verifier and tls-rustls-ring-platform-verifier to enable platform's native CA certificates provided by rustls-platform-verifier.
• Removes dependency on rustls-native-certs (since rustls-platform-verifier is now recommended over it instead).
• Makes tls-rustls-ring-native-roots feature flag an alias to tls-rustls-ring-platform-verifier for backwards compatibility reasons.

[manifest]

Should feature flag tls-rustls-aws-lc-rs be renamed into tls-rustls-aws-lc-rs-webpki to match tls-rustls-ring-webpki?

[curtisleefulton]

Should feature flag tls-rustls-aws-lc-rs be renamed into tls-rustls-aws-lc-rs-webpki to match tls-rustls-ring-webpki?

I vote yes

[curtisleefulton]

I'm suggesting a new feature on top of this PR. See manifest#2

Feature tls-rustls-no-provider-platform-verifier installs no crypto library and uses CryptoProvider::get_default() instead. This will work the same as Reqwest's rustls-tls-native-roots-no-provider feature, when coupled with rustls-platform-verifier crate .

See https://docs.rs/rustls/latest/rustls/crypto/struct.CryptoProvider.html#using-the-per-process-default-cryptoprovider :

libraries should use ClientConfig::builder()/ServerConfig::builder() or otherwise rely on the CryptoProvider::get_default() provider.

[manifest]

I've updated this PR to use the latest sqlx version.