gh-98513: Test abstract methods of some collections types (GH-98516)

(cherry picked from commit a309ad9)

Co-authored-by: Nikita Sobolev <mail@sobolevn.me>

Author: miss-islington

Lib/test/test_collections.py

@@ -788,6 +788,8 @@ def throw(self, typ, val=None, tb=None):
             def __await__(self):
                 yield
 
+        self.validate_abstract_methods(Awaitable, '__await__')
+
         non_samples = [None, int(), gen(), object()]
         for x in non_samples:
             self.assertNotIsInstance(x, Awaitable)
@@ -838,6 +840,8 @@ def throw(self, typ, val=None, tb=None):
             def __await__(self):
                 yield
 
+        self.validate_abstract_methods(Coroutine, '__await__', 'send', 'throw')
+
         non_samples = [None, int(), gen(), object(), Bar()]
         for x in non_samples:
             self.assertNotIsInstance(x, Coroutine)
@@ -1921,6 +1925,7 @@ def test_ByteString(self):
             self.assertFalse(issubclass(sample, ByteString))
         self.assertNotIsInstance(memoryview(b""), ByteString)
         self.assertFalse(issubclass(memoryview, ByteString))
+        self.validate_abstract_methods(ByteString, '__getitem__', '__len__')
 
     def test_MutableSequence(self):
         for sample in [tuple, str, bytes]: