Update category-anticensorship (#2651)

* Add sing-box.app in category-anticensorship

* Add trojan-gfw.github.io

* Add metacubex.one

data/category-anticensorship

@@ -38,6 +38,7 @@ proxifier.com
 psiphon.ca
 psiphon3.com
 sagernet.org
+sing-box.app
 shadowsocks.org
 sspanel.net
 stunnel.org
@@ -53,4 +54,6 @@ whonix.org
 wikileaks.org
 wireguard.com
 xtls.github.io
+trojan-gfw.github.io
 zeronet.io
+metacubex.one