tox: Remove py37 entries

We no longer support Python 3.7.

Signed-off-by: Stephen Finucane <[email protected]>

Author: stephenfin

tox.ini

@@ -1,6 +1,6 @@
 [tox]
 minversion = 2.0
-envlist = py{37,38,39}-click{7,8,8-async},py{310,311}-click{8,8-async},style,docs
+envlist = py{38,39}-click{7,8,8-async},py{310,311}-click{8,8-async},style,docs
 
 [testenv]
 setenv =