Issue #13959: Deprecate imp.get_suffixes() for new attributes on

importlib.machinery that provide the suffix details for import.
The attributes were not put on imp so as to compartmentalize
everything importlib needs for setting up imports in
importlib.machinery.

This also led to an indirect deprecation of inspect.getmoduleinfo() as
it directly returned imp.get_suffix's returned tuple which no longer
makes sense.

Lib/importlib/test/source/test_path_hook.py

@@ -1,6 +1,6 @@
 from . import util as source_util
 
-from importlib import _bootstrap
+from importlib import machinery
 import imp
 import unittest
 
@@ -10,8 +10,8 @@ class PathHookTest(unittest.TestCase):
     """Test the path hook for source."""
 
     def path_hook(self):
-        return _bootstrap.FileFinder.path_hook((_bootstrap.SourceFileLoader,
-            _bootstrap._SOURCE_SUFFIXES, True))
+        return machinery.FileFinder.path_hook((machinery.SourceFileLoader,
+            machinery.SOURCE_SUFFIXES, True))
 
     def test_success(self):
         with source_util.create_modules('dummy') as mapping: