follow Phabricator update 2020 Week 5;

--- a/src/Pure/Tools/phabricator.scala	Wed Feb 05 20:17:00 2020 +0000
+++ b/src/Pure/Tools/phabricator.scala	Fri Feb 07 20:26:31 2020 +0100
@@ -288,13 +288,13 @@
         echo "Cloning distribution repositories:"
 
         git clone --branch stable https://github.com/phacility/libphutil.git
-        git -C libphutil reset --hard 1750586fdc50a6cd98adba4aa2f5a7649bd91dbe
+        git -C libphutil reset --hard 034cf7cc39940b935e83923dbb1bacbcfe645a85
 
         git clone --branch stable https://github.com/phacility/arcanist.git
-        git -C arcanist reset --hard bac2028421a4be6e34e08764bbbda49e68b3a604
+        git -C arcanist reset --hard 729100955129851a52588cdfd9b425197cf05815
 
         git clone --branch stable https://github.com/phacility/phabricator.git
-        git -C phabricator reset --hard c4b4a53cad7722f031b725f8b41511e9d341d033
+        git -C phabricator reset --hard 46fcd135ae681bb90a1282114fb2147ab21e4f34
       """).check
 
     val config = Config(name, root_path)