fix provider error

mtproxy-entrypoint.sh

@@ -25,7 +25,7 @@ set_config(){
 		sed -i 's/domain="[0-9A-z\.\-]*"/domain="'$domain'"/' $mtp_config
 	fi
 	if [ "$provider" ] && [[ "$provider" =~ ^[1-2]$ ]]; then
-		sed -i 's/provider=[0-9]\+/cat /='$provider'/' $mtp_config
+		sed -i 's/provider=[0-9]\+/provider="'$provider'"/' $mtp_config
 	fi
 }