update rustls

Author: jbr

Cargo.toml

@@ -18,9 +18,9 @@ appveyor = { repository = "async-std/async-tls" }
 [dependencies]
 futures-io = "0.3.5"
 futures-core = "0.3.5"
-rustls = "0.18.0"
-webpki = { version = "0.21.2", optional = true }
-webpki-roots = { version = "0.20.0", optional = true }
+rustls = "0.19.0"
+webpki = { version = "0.21.3", optional = true }
+webpki-roots = { version = "0.21.0", optional = true }
 
 [features]
 default = ["client", "server"]