pub fn with_enabled_roots(self) -> Self {
        let config = self;

        #[cfg(feature = "tls-native-roots")]
        let config = config.with_native_roots();
        #[cfg(feature = "tls-webpki-roots")]
        let config = config.with_webpki_roots();

        config
    }
Activates all TLS roots enabled through `tls-*-roots` feature flags
tonic/src/transport/channel/tls.rs