IsReferenceOrContainsReferences update (#9986)

* IsReferenceOrContainsReferences update
---------
Co-authored-by: Genevieve Warren <[email protected]>

Author: AaronRobinsonMSFT

xml/System.Runtime.CompilerServices/RuntimeHelpers.xml

@@ -767,10 +767,10 @@ This method is intended for compiler use rather than use directly in code. `T` m
       <Parameters />
       <Docs>
         <typeparam name="T">The type.</typeparam>
-        <summary>Returns a value that indicates whether the specified type is a reference type or a value type that contains references.</summary>
+        <summary>Returns a value that indicates whether the specified type is a reference type or a value type that contains references or by-refs.</summary>
         <returns>
-          <see langword="true" /> if the given type is reference type or value type that contains references; otherwise, <see langword="false" />.</returns>
-        <remarks>To be added.</remarks>
+          <see langword="true" /> if the given type is a reference type or a value type that contains references or by-refs; otherwise, <see langword="false" />.</returns>
+        <remarks>Prior to .NET 9, this API doesn't support types that can contain by-refs.</remarks>
       </Docs>
     </Member>
     <Member MemberName="OffsetToStringData">