Bump mypy to 1.15.0 (#13473)

stubs/pyasn1/@tests/stubtest_allowlist.txt

@@ -1,7 +1,3 @@
 # typeshed typing differences with runtime collections.OrderedDict and builtins.dict
 pyasn1.codec.native.encoder.SequenceEncoder.protoDict
 pyasn1.codec.native.encoder.SetEncoder.protoDict
-
-# Attempted "__ne__" operation on ASN.1 schema object
-pyasn1.type.base
-pyasn1.type.univ

stubs/pyasn1/pyasn1/type/univ.pyi

@@ -88,9 +88,7 @@ class Boolean(Integer):
     namedValues: namedval.NamedValues
     typeId: int
 
-SizedIntegerBase = int
-
-class SizedInteger(SizedIntegerBase):
+class SizedInteger(int):
     bitLength: int | None
     leadingZeroBits: int | None
     def setBitLength(self, bitLength): ...