Bug 27865: Tor Browser 8.5a2 is crashing on Windows

We disable the usage of MOZILLA_OFFICIAL again for Windows platforms as
Tor Browser is crashing otherwise. The underlying reason is likely the
same as in https://bugzilla.mozilla.org/show_bug.cgi?id=1470772.

projects/firefox/mozconfig-windows-i686

@@ -10,7 +10,6 @@ ac_add_options --enable-default-toolkit=cairo-windows
 mk_add_options MOZ_OBJDIR=@TOPSRCDIR@/obj-mingw
 mk_add_options MOZ_APP_DISPLAYNAME="Tor Browser"
 mk_add_options MOZILLA_OFFICIAL=1
-export MOZILLA_OFFICIAL=1
 mk_add_options BUILD_OFFICIAL=1
 
 ac_add_options --disable-debug

projects/firefox/mozconfig-windows-x86_64

@@ -10,7 +10,6 @@ ac_add_options --enable-default-toolkit=cairo-windows
 mk_add_options MOZ_OBJDIR=@TOPSRCDIR@/obj-mingw
 mk_add_options MOZ_APP_DISPLAYNAME="Tor Browser"
 mk_add_options MOZILLA_OFFICIAL=1
-export MOZILLA_OFFICIAL=1
 mk_add_options BUILD_OFFICIAL=1
 
 ac_add_options --disable-debug