Remove constraint that prevented aiodns from being installed on Windows

As of aiodns 3.3.0 SelectorEventLoop is no longer required when using
pycares 4.7.0 or later

closes #8121

Author: bdraco

setup.cfg

@@ -66,8 +66,7 @@ install_requires =
 
 [options.extras_require]
 speedups =
-  # required c-ares (aiodns' backend) will not build on windows
-  aiodns >= 3.2.0; sys_platform=="linux" or sys_platform=="darwin"
+  aiodns >= 3.3.0
   Brotli; platform_python_implementation == 'CPython'
   brotlicffi; platform_python_implementation != 'CPython'