add testAvoidFalseNonOverlappingEqualityCheckInLoop3

Author: tyralla

test-data/unit/check-narrowing.test

@@ -2472,6 +2472,15 @@ while True:
     x = B()
 [builtins fixtures/primitives.pyi]
 
+[case testAvoidFalseNonOverlappingEqualityCheckInLoop3]
+# flags: --strict-equality
+
+for y in [1.0]:
+    if y is not None or y != "None":  # E: Non-overlapping equality check (left operand type: "float", right operand type: "Literal['None']")
+        ...
+
+[builtins fixtures/primitives.pyi]
+
 [case testNarrowPromotionsInsideUnions1]
 
 from typing import Union