remove _unicodefun #2198
Description
Same as pallets/werkzeug#1760, Python 3.7+ picks UTF-8 instead of ASCII for misconfigured systems. Since we are dropping Python 3.6, we can drop the check.
~
❯ LANG= LC_ALL= python3.6 -c 'import locale, codecs; print(codecs.lookup(locale.getpreferredencoding()).name)'
ascii
~
❯ LANG= LC_ALL= python3.7 -c 'import locale, codecs; print(codecs.lookup(locale.getpreferredencoding()).name)'
utf-8