Fix: only use Openvpn fast-io when using UDP

internal/provider/torguard/openvpnconf.go

@@ -37,7 +37,6 @@ func (t *Torguard) BuildConf(connection models.OpenVPNConnection,
 		"tun-mtu-extra 32",
 		"mssfix " + strconv.Itoa(int(settings.MSSFix)),
 		"reneg-sec 0",
-		"fast-io",
 		"key-direction 1",
 		"script-security 2",
 		"ncp-disable",
@@ -67,6 +66,10 @@ func (t *Torguard) BuildConf(connection models.OpenVPNConnection,
 		lines = append(lines, "user "+username)
 	}
 
+	if connection.Protocol == constants.UDP {
+		lines = append(lines, "fast-io")
+	}
+
 	lines = append(lines, utils.WrapOpenvpnCA(
 		constants.TorguardCertificate)...)
 	lines = append(lines, utils.WrapOpenvpnTLSAuth(