tox: remove py2 builds (#39299)

tox.ini

@@ -1,6 +1,6 @@
 [tox]
 toxworkdir = {env:TMPDIR:/tmp}/tox-{env:USER}/wcs/{env:BRANCH_NAME:}
-envlist = py2-pylint-coverage,py3
+envlist = py3-pylint-coverage
 
 [testenv]
 sitepackages = true
@@ -16,8 +16,7 @@ setenv =
 passenv =
     USER
 deps =
-    py2: pytest
-    py3: pytest>=3.6,<5
+    pytest>=3.6,<5
     pytest-mock
     pytest-cov
     pytest-django
@@ -38,7 +37,7 @@ deps =
     django-ratelimit<3
     pyproj
     pylint<1.8
-    py3: Quixote>=3.0
+    Quixote>=3.0
 commands =
     py.test -v {env:COVERAGE:} --junitxml=junit-{envname}.xml {posargs:tests/}
     pylint: ./pylint.sh wcs/