brew: add DBUS_SESSION_BUS_ADDRESS copy

bin/brew

@@ -64,7 +64,7 @@ HOMEBREW_LIBRARY="${HOMEBREW_REPOSITORY}/Library"
 
 # Copy and export all HOMEBREW_* variables previously mentioned in
 # manpage or used elsewhere by Homebrew.
-for VAR in BROWSER DISPLAY EDITOR NO_COLOR PATH TMUX
+for VAR in BROWSER DISPLAY EDITOR NO_COLOR PATH TMUX DBUS_SESSION_BUS_ADDRESS
 do
   # Skip if variable value is empty.
   [[ -z "${!VAR}" ]] && continue