Enable test_bytes from stdlib (#948)

Author: BCSharp

Src/IronPythonTest/Cases/CPythonCasesManifest.ini

@@ -197,9 +197,6 @@ Ignore=true
 [CPython.test_bufio]
 RetryCount=2
 
-[CPython.test_bytes] # IronPython.test_bytes_stdlib
-Ignore=true
-
 [CPython.test_bz2] # IronPython.test_bz2_stdlib
 Ignore=true
 

Src/StdLib/Lib/test/test_bytes.py

@@ -754,6 +754,7 @@ def __bytes__(self):
         self.assertIs(type(BytesSubclass(A())), BytesSubclass)
 
     # Test PyBytes_FromFormat()
+    @unittest.skipIf(sys.implementation.name=='ironpython', 'CPython-specific test depending on ctypes.pythonapi')
     def test_from_format(self):
         test.support.import_module('ctypes')
         from ctypes import pythonapi, py_object, c_int, c_char_p