fix(setup): disallow python 3.6 for pip install (#11825)

* fix(setup): disallow python 3.6 for pip install

* remove old py constraint

setup.py

@@ -22,9 +22,6 @@
 
 from setuptools import find_packages, setup
 
-if sys.version_info < (3, 6):
-    sys.exit("Sorry, Python < 3.6 is not supported")
-
 BASE_DIR = os.path.abspath(os.path.dirname(__file__))
 
 PACKAGE_JSON = os.path.join(BASE_DIR, "superset-frontend", "package.json")
@@ -138,7 +135,7 @@ def get_git_sha():
         "thumbnails": ["Pillow>=7.0.0, <8.0.0"],
         "vertica": ["sqlalchemy-vertica-python>=0.5.9, < 0.6"],
     },
-    python_requires="~=3.6",
+    python_requires="~=3.7",
     author="Apache Software Foundation",
     author_email="[email protected]",
     url="https://superset.apache.org/",