Allow TLS enabled connections when providing an established channel (#…

…526)

Co-authored-by: Fabian Fett <fabianfett@apple.com>

Sources/PostgresNIO/Connection/PostgresConnection+Configuration.swift

@@ -192,9 +192,22 @@ extension PostgresConnection {
         /// - Parameters:
         ///   - channel: The `NIOCore/Channel` to use. The channel must already be active and connected to an
         ///     endpoint (i.e. `NIOCore/Channel/isActive` must be `true`).
-        ///   - tls: The TLS mode to use. Defaults to ``TLS-swift.struct/disable``.
+        ///   - tls: The TLS mode to use.
+        public init(establishedChannel channel: Channel, tls: PostgresConnection.Configuration.TLS, username: String, password: String?, database: String?) {
+            self.init(endpointInfo: .configureChannel(channel), tls: tls, username: username, password: password, database: database)
+        }
+
+        /// Create a configuration for establishing a connection to a Postgres server over a preestablished
+        /// `NIOCore/Channel`.
+        ///
+        /// This is provided for calling code which wants to manage the underlying connection transport on its
+        /// own, such as when tunneling a connection through SSH.
+        ///
+        /// - Parameters:
+        ///   - channel: The `NIOCore/Channel` to use. The channel must already be active and connected to an
+        ///     endpoint (i.e. `NIOCore/Channel/isActive` must be `true`).
         public init(establishedChannel channel: Channel, username: String, password: String?, database: String?) {
-            self.init(endpointInfo: .configureChannel(channel), tls: .disable, username: username, password: password, database: database)
+            self.init(establishedChannel: channel, tls: .disable, username: username, password: password, database: database)
         }
 
         // MARK: - Implementation details