Remove 500 patch. 1.7.0 upgrade.

While 1.7.0 exhibits a similar issue, we would need to re-verify and
re-patch this library with a new 1.7.0 monkeypatch.

This is ultimately only an annoyance.  It only occours when we've
already 500'd, and this just means we get a second 500.  As such it's
not critical.

pinaxcon/monkey_patch.py

@@ -11,7 +11,6 @@ class MonkeyPatchMiddleware(object):
 
 def do_monkey_patch():
     patch_speaker_profile_form()
-    fix_sitetree_check_access_500s()
     patch_stripe_payment_form()
 
     # Remove this function from existence
@@ -31,25 +30,6 @@ def patch_speaker_profile_form():
     fields["accessibility"].widget = widgets.AceMarkdownEditor()
 
 
-def fix_sitetree_check_access_500s():
-    ''' django-sitetree has a bug: https://github.com/idlesign/django-sitetree/pull/167/files
-    -- it swallows the cause of all 500 errors. This swallows KeyErrors from
-    the failing function. '''
-
-    from sitetree.sitetreeapp import SiteTree
-
-    old_check_access = SiteTree.check_access
-
-    @wraps(SiteTree.check_access)
-    def check_access(self, *a, **k):
-        try:
-            return old_check_access(self, *a, **k)
-        except KeyError:
-            return False
-
-    SiteTree.check_access = check_access
-
-
 def patch_stripe_payment_form():  # noqa: C901
 
     import inspect  # Oh no.