Update CI to tox 4

tox-gh-actions now supports tox 4.

Also fix `passenv` error with whitespace.

.github/workflows/ci.yml

@@ -39,8 +39,7 @@ jobs:
                   dbus-x11 libnotify-bin \
                   xwayland libxcb-composite0-dev libxcb-icccm4-dev libxcb-res0-dev \
                   libxcb-render0-dev libxcb-res0-dev libxcb-xfixes0-dev vlc volumeicon-alsa
-                sudo pip -q install meson PyGObject
-                pip -q install "tox<4" tox-gh-actions 
+                sudo pip -q install meson PyGObject tox tox-gh-actions
             - name: Build wayland
               run: |
                 wget -q --no-check-certificate https://wayland.freedesktop.org/releases/wayland-$WAYLAND.tar.xz

tox.ini

@@ -1,7 +1,8 @@
 [tox]
 skip_missing_interpreters = True
 skipsdist=True
-minversion = 1.8
+minversion = 4.0.12
+allowlist_externals={toxinidir}/scripts/ffibuild
 envlist =
     pypy3,
     py39,
@@ -20,7 +21,7 @@ envlist =
 # that our tests use.
 setenv = LC_CTYPE = en_US.UTF-8
 # Pass Display down to have it for the tests available
-passenv = DISPLAY WAYLAND_DISPLAY
+passenv = DISPLAY,WAYLAND_DISPLAY
 whitelist_externals=convert
 # xcffib has to be installed before cairocffi
 deps =