Remove outdated PyPy stdlib overrides

docs/changelog/2426.feature.rst

@@ -0,0 +1 @@
+Drop support for PyPy3.6, PyPy3.7 which are no longer supported upstream.

docs/installation.rst

@@ -89,7 +89,7 @@ Python and OS Compatibility
 virtualenv works with the following Python interpreter implementations:
 
 - `CPython <https://www.python.org/>`_ versions 2.7, 3.5, 3.6, 3.7, 3.8, 3.9, 3.10
-- `PyPy <https://pypy.org/>`_ 2.7 and 3.5+.
+- `PyPy <https://pypy.org/>`_ 2.7, 3.6, 3.7, 3.8, 3.9
 
 This means virtualenv works on the latest patch version of each of these minor versions. Previous patch versions are
 supported on a best effort approach.

src/virtualenv/create/via_global_ref/builtin/pypy/pypy3.py

@@ -20,11 +20,6 @@ def exe_names(cls, interpreter):
 class PyPy3Posix(PyPy3, PosixSupports):
     """PyPy 3 on POSIX"""
 
-    @property
-    def stdlib(self):
-        """PyPy3 respects sysconfig only for the host python, virtual envs is instead lib/pythonx.y/site-packages"""
-        return self.dest / "lib" / f"pypy{self.interpreter.version_release_str}" / "site-packages"
-
     @classmethod
     def _shared_libs(cls, python_dir):
         # glob for libpypy3-c.so, libpypy3-c.dylib, libpypy3.9-c.so ...
@@ -64,18 +59,6 @@ class Pypy3Windows(PyPy3, WindowsSupports):
     def less_v37(self):
         return self.interpreter.version_info.minor < 7
 
-    @property
-    def stdlib(self):
-        """PyPy3 respects sysconfig only for the host python, virtual envs is instead Lib/site-packages"""
-        if self.less_v37:
-            return self.dest / "site-packages"
-        return self.dest / "Lib" / "site-packages"
-
-    @property
-    def bin_dir(self):
-        """PyPy3 needs to fallback to pypy definition"""
-        return self.dest / "Scripts"
-
     @classmethod
     def _shared_libs(cls, python_dir):
         # glob for libpypy*.dll and libffi*.dll