feat: microoptimize _collections_abc._check_methods

We can reduce the number of attribute lookups requried here. 

I also think we can speed it up a little bit more if we make `methods` arg a packed tuple instead of an unpacked one since we can bypass the additional tuple creation at the time of each call

Seeking input on that before I implement the same

Author: BobTheBuidler

Lib/_collections_abc.py

@@ -106,11 +106,11 @@ async def _ag(): yield
 ### ONE-TRICK PONIES ###
 
 def _check_methods(C, *methods):
-    mro = C.__mro__
+    mro_dicts = [B.__dict__ for B in C.__mro__]
     for method in methods:
-        for B in mro:
-            if method in B.__dict__:
-                if B.__dict__[method] is None:
+        for base_dict in mro_dicts:
+            if method in base_dict:
+                if base_dict[method] is None:
                     return NotImplemented
                 break
         else: