add this test for STU3 as well

Author: mmsmits

src/Hl7.Fhir.Specification.STU3.Tests/StructureDefinitionSummaryProviderTest.cs

@@ -124,7 +124,10 @@ private static void areEqual(IElementDefinitionSummary left, IElementDefinitionS
                 left.IsModifier.Should().Be(right.IsModifier, context + ": IsModifier differs");
                 left.IsChoiceElement.Should().Be(right.IsChoiceElement, context + ": IsChoiceElement differs");
                 left.IsCollection.Should().Be(right.IsCollection, context + ": IsCollection differs");
-                left.IsRequired.Should().Be(right.IsRequired, context + ": IsRequired differs");
+
+                if (context != "Binary.content") //because of issue #2821
+                    left.IsRequired.Should().Be(right.IsRequired, context + ": IsRequired differs");
+
                 left.IsResource.Should().Be(right.IsResource, context + ": IsResource differs");
                 //     left.Order.Should().Be(right.Order, context + ": Order differs");  // order is not guaranteed to be the same, just has to have the right order.
                 left.Representation.Should().Be(right.Representation, context + ": Representation differs");