Update subscribe.lua

Fix missing `tls_flow` when using new config of flow='xtls-rprx-vision' and security='tls'

luci-app-ssr-plus/root/usr/share/shadowsocksr/subscribe.lua

@@ -364,6 +364,7 @@ local function processData(szType, content)
 		result.packet_encoding = packet_encoding
 		result.tls = (params.security == "tls") and "1" or "0"
 		result.tls_host = params.sni
+		result.tls_flow = params.flow
 		result.xtls = params.security == "xtls" and "1" or nil
 		result.vless_flow = params.flow
 		result.fingerprint = params.fp