Sync trove classifiers with tox.ini (#1341)

* Sync trove classifiers with tox.ini

* No need for Python 3 condition anymore

Author: ulgens

setup.py

@@ -19,8 +19,7 @@
     "coveralls",
     "mock",
     "pytz",
-    "django-filter<2;python_version<'3'",
-    "django-filter>=2;python_version>='3'",
+    "django-filter>=2",
     "pytest-django>=3.3.2",
 ] + rest_framework_require
 
@@ -45,25 +44,26 @@
         "Development Status :: 3 - Alpha",
         "Intended Audience :: Developers",
         "Topic :: Software Development :: Libraries",
-        "Programming Language :: Python :: 2",
-        "Programming Language :: Python :: 2.7",
         "Programming Language :: Python :: 3",
         "Programming Language :: Python :: 3.6",
         "Programming Language :: Python :: 3.7",
         "Programming Language :: Python :: 3.8",
+        "Programming Language :: Python :: 3.9",
+        "Programming Language :: Python :: 3.10",
         "Programming Language :: Python :: Implementation :: PyPy",
         "Framework :: Django",
-        "Framework :: Django :: 1.11",
         "Framework :: Django :: 2.2",
         "Framework :: Django :: 3.0",
+        "Framework :: Django :: 3.1",
+        "Framework :: Django :: 3.2",
+        "Framework :: Django :: 4.0",
     ],
     keywords="api graphql protocol rest relay graphene",
     packages=find_packages(exclude=["tests", "examples", "examples.*"]),
     install_requires=[
-        "six>=1.10.0",
         "graphene>=2.1.7,<3",
         "graphql-core>=2.1.0,<3",
-        "Django>=1.11",
+        "Django>=2.2",
         "singledispatch>=3.4.0.3",
         "promise>=2.1",
         "text-unidecode",