change flake8 rule name to RPY

Author: rmorshea

setup.py

@@ -18,8 +18,8 @@
 package = {
     "name": name,
     "packages": setuptools.find_packages(exclude=["tests*"]),
-    "entry_points": {"flake8.extension": ["REACTPY=reactpy_flake8:plugin"]},
-    "python_requires": ">=3.6",
+    "entry_points": {"flake8.extension": ["RPY=reactpy_flake8:plugin"]},
+    "python_requires": ">=3.7",
     "description": "Flake8 plugin to enforce the rules of hooks for ReactPy",
     "author": "Ryan Morshead",
     "author_email": "ryan.morshead@gmail.com",