PY-86002 Revert also PY-25989 PY-84544 to fix new test failures after the revert to weak unions

Namely, `generics_basic.py` in the conformance test suite and
Py3TypeCheckerInspectionTest.testTypeVarWidening.

Revert 07803c6243370d55df0d870e2e32b38170c1fb49


(cherry picked from commit 9c334ef32597be1d1e8fbc3251ac267be46555c8)

IJ-MR-184619

GitOrigin-RevId: 4b2440c973d9c7a7a42590665bd473c4e7a4c9cf

python/testSrc/com/jetbrains/python/inspections/Py3TypeCheckerInspectionTest.java

@@ -3332,33 +3332,4 @@ public class Py3TypeCheckerInspectionTest extends PyInspectionTestCase {
                    var: Template = Concrete()
                    """);
   }
-
-  // PY-25989 PY-84544
-  public void testTypeVarWidening() {
-    myFixture.enableInspections(PyAssertTypeInspection.class);
-    doTestByText("""
-                   from collections.abc import Iterable
-                   from typing import assert_type
-
-
-                   # PY-84544
-                   def foo(iterable: Iterable[int] | Iterable[str]) -> None:
-                       assert_type(next(iter(iterable)), int | str)
-
-
-                   # PY-25989
-                   assert_type(max(1, 2.6), float)
-                   assert_type(max(2.6, 1), float)
-                   max(1, <warning descr="Expected type 'int' (matched generic type 'SupportsRichComparisonT ≤: SupportsDunderLT[Any] | SupportsDunderGT[Any]'), got 'object' instead">object()</warning>)    
-
-
-                   def bar[T: int, str](v1: T, v2: T) -> T:
-                       if (bool(input())):
-                           return v1
-                       return v2
-
-
-                   _ = bar(1, <warning descr="Expected type 'int' (matched generic type 'T ≤: int'), got 'str' instead">"a"</warning>)
-                   """);
-  }
 }

python/testSrc/com/jetbrains/python/inspections/PyTypeCheckerInspectionTest.java

@@ -1347,10 +1347,7 @@ public class PyTypeCheckerInspectionTest extends PyInspectionTestCase {
                            def accepts_anything(x: str) -> None:
                                pass
 
-                           # Bug: Expected error.
-                           # `Callable[[str], None]` is assignable to `Callable[[int | str], None]`.
-                           # Thus, substitution `T` -> `int | str` is considered valid.
-                           func(42, accepts_anything)""")
+                           func(42, <warning descr="Expected type '(int) -> None' (matched generic type '(T) -> None'), got '(x: str) -> None' instead">accepts_anything</warning>)""")
     );
   }