CI: pin chardet<7 until orange3 release/oldest supports chardet 7

Author: stuart-cls

tox.ini

@@ -33,6 +33,8 @@ deps =
     oldest: spectral~=0.22.3
     oldest: lmfit==1.3.2
     oldest: pillow==9.0.0
+    oldest: chardet<7  # until oldest orange3 supports chardet 7
+    released: chardet<7  # until released orange3 supports chardet 7
     latest: https://github.com/quasars/orange-spectroscopy/archive/refs/heads/master.zip#egg=orange-spectroscopy
     latest: https://github.com/biolab/orange3/archive/refs/heads/master.zip#egg=orange3
     latest: https://github.com/biolab/orange-canvas-core/archive/refs/heads/master.zip#egg=orange-canvas-core