[fix] Fix a crash for class decorators mistaken for class attributes (#10362) (#10363)

Closes #10105

(cherry picked from commit 1812899)

Co-authored-by: Pierre Sassoulas <pierre.sassoulas@gmail.com>

Author: github-actions[bot]

doc/whatsnew/fragments/10105.bugfix

@@ -0,0 +1,3 @@
+Fixed a crash when importing a class decorator that did not exist with the same name than a class attribute after the class definition.
+
+Closes #10105

pylint/checkers/variables.py

@@ -2448,7 +2448,7 @@ def _is_only_type_assignment(
         node_frame = node.frame()
 
         parent = node
-        while parent is not defstmt_frame.parent:
+        while parent not in {defstmt_frame.parent, None}:
             parent_scope = parent.scope()
 
             # Find out if any nonlocals receive values in nested functions

tests/functional/r/regression_02/regression_10105.py

@@ -0,0 +1,9 @@
+# pylint: disable=too-few-public-methods,missing-docstring,used-before-assignment,import-error,unused-import
+# pylint: disable=wrong-import-position
+
+
+@decorator
+class DecoratedClass:
+    decorator: int
+
+import decorator