Drop support for PyPy and psycopg2cffi [skip ci]

issue11330
review386371003

setup.py

@@ -92,7 +92,6 @@ setup(name=name,
         'Programming Language :: Python :: 3.9',
         'Programming Language :: Python :: 3.10',
         'Programming Language :: Python :: Implementation :: CPython',
-        'Programming Language :: Python :: Implementation :: PyPy',
         'Topic :: Office/Business',
         ],
     platforms='any',

tox.ini

@@ -1,5 +1,5 @@
 [tox]
-envlist = py37,py38,py39,py310,pypy3
+envlist = py37,py38,py39,py310
 
 [testenv]
 commands =