Upgrade system and package versions

- Alpine from 3.12 to 3.13 and:
- Openvpn from 2.4.10 to 2.5.1
- Unbound from 1.10.1 to 1.13.0
- Iptables from 1.8.4 to 1.8.6

internal/provider/privatevpn.go

@@ -127,7 +127,8 @@ func (p *privatevpn) BuildConf(connection models.OpenVPNConnection,
 		fmt.Sprintf("auth-user-pass %s", constants.OpenVPNAuthConf),
 		fmt.Sprintf("proto %s", connection.Protocol),
 		fmt.Sprintf("remote %s %d", connection.IP, connection.Port),
-		fmt.Sprintf("cipher %s", settings.Cipher),
+		"data-ciphers-fallback " + settings.Cipher,
+		"data-ciphers " + settings.Cipher,
 		fmt.Sprintf("auth %s", settings.Auth),
 	}
 	if connection.Protocol == constants.UDP {