[ty] Fix method calls on subclasses of Any (#23248)

## Summary

Another small win in terms of typing conformance. This should fix the
last remaining test in
[`specialtypes_any.py`](https://shark.fish/typing-conformance-report/specialtypes_any.html)

## Ecosystem

The new diagnostics look like true positives (in our current strict
interpretation of LSP checks)

## Test Plan

New Markdown test

Author: sharkdp

crates/ty_python_semantic/resources/mdtest/call/methods.md

@@ -233,6 +233,21 @@ def _(a: object, b: SupportsStr, c: Falsy, d: AlwaysFalsy, e: None, f: Foo | Non
     f.__str__()
 ```
 
+## Method calls on subclasses of `Any`
+
+```py
+from typing_extensions import assert_type, Any
+
+class SubclassOfAny(Any):
+    def method(self) -> int:
+        return 1
+
+a = SubclassOfAny()
+assert_type(a.method(), int)
+
+assert_type(a.non_existing_method(), Any)
+```
+
 ## Error cases: Calling `__get__` for methods
 
 The `__get__` method on `types.FunctionType` has the following overloaded signature in typeshed:

crates/ty_python_semantic/src/place.rs

@@ -15,7 +15,7 @@ use crate::semantic_index::{DeclarationWithConstraint, global_scope, use_def_map
 use crate::types::{
     ApplyTypeMappingVisitor, DynamicType, KnownClass, MaterializationKind, MemberLookupPolicy,
     Truthiness, Type, TypeAndQualifiers, TypeQualifiers, UnionBuilder, UnionType, binding_type,
-    declaration_type, todo_type,
+    declaration_type,
 };
 use crate::{Db, FxOrderSet, Program};
 
@@ -174,13 +174,6 @@ impl<'db> Place<'db> {
         Place::Defined(DefinedPlace::new(ty.into()).with_origin(TypeOrigin::Declared))
     }
 
-    /// Constructor that creates a [`Place`] with a [`crate::types::TodoType`] type
-    /// and definedness [`Definedness::AlwaysDefined`].
-    #[allow(unused_variables)] // Only unused in release builds
-    pub(crate) fn todo(message: &'static str) -> Self {
-        Place::Defined(DefinedPlace::new(todo_type!(message)))
-    }
-
     pub(crate) fn is_undefined(&self) -> bool {
         matches!(self, Place::Undefined)
     }
@@ -675,17 +668,6 @@ pub(crate) struct PlaceAndQualifiers<'db> {
 }
 
 impl<'db> PlaceAndQualifiers<'db> {
-    /// Constructor that creates a [`PlaceAndQualifiers`] instance with a [`TodoType`] type
-    /// and no qualifiers.
-    ///
-    /// [`TodoType`]: crate::types::TodoType
-    pub(crate) fn todo(message: &'static str) -> Self {
-        Self {
-            place: Place::todo(message),
-            qualifiers: TypeQualifiers::empty(),
-        }
-    }
-
     pub(crate) fn unbound() -> Self {
         Self::default()
     }

crates/ty_python_semantic/src/types/class.rs

@@ -6111,9 +6111,10 @@ impl<'db, I: Iterator<Item = ClassBase<'db>>> MroLookup<'db, I> {
                     // Skip over these very special class bases that aren't really classes.
                 }
                 ClassBase::Dynamic(_) => {
-                    return InstanceMemberResult::Done(PlaceAndQualifiers::todo(
-                        "instance attribute on class with dynamic base",
-                    ));
+                    // We already return the dynamic type for class member lookup, so we can
+                    // just return unbound here (to avoid having to build a union of the
+                    // dynamic type with itself).
+                    return InstanceMemberResult::Done(PlaceAndQualifiers::unbound());
                 }
                 ClassBase::Class(class) => {
                     if let member @ PlaceAndQualifiers {