Try to workaround the Mono test failures

Author: tannergooding

src/libraries/System.Private.CoreLib/src/System/Numerics/Plane.cs

@@ -204,6 +204,7 @@ public static Plane Transform(Plane plane, Quaternion rotation)
         /// <returns><see langword="true" /> if <paramref name="value1" /> and <paramref name="value2" /> are equal; otherwise, <see langword="false" />.</returns>
         /// <remarks>Two <see cref="Plane" /> objects are equal if their <see cref="Normal" /> and <see cref="D" /> fields are equal.
         /// The <see cref="op_Equality" /> method defines the operation of the equality operator for <see cref="Plane" /> objects.</remarks>
+        [Intrinsic]
         [MethodImpl(MethodImplOptions.AggressiveInlining)]
         public static bool operator ==(Plane value1, Plane value2) => value1.AsVector128() == value2.AsVector128();
 

src/libraries/System.Private.CoreLib/src/System/Numerics/Quaternion.cs

@@ -129,6 +129,7 @@ public float this[int index]
         /// <returns><see langword="true" /> if the two quaternions are equal; otherwise, <see langword="false" />.</returns>
         /// <remarks>Two quaternions are equal if each of their corresponding components is equal.
         /// The <see cref="op_Equality" /> method defines the operation of the equality operator for <see cref="Quaternion" /> objects.</remarks>
+        [Intrinsic]
         [MethodImpl(MethodImplOptions.AggressiveInlining)]
         public static bool operator ==(Quaternion value1, Quaternion value2) => value1.AsVector128() == value2.AsVector128();
 

src/libraries/System.Private.CoreLib/src/System/Numerics/Vector4.cs

@@ -142,6 +142,7 @@ public float this[int index]
         /// <param name="right">The second vector to compare.</param>
         /// <returns><see langword="true" /> if <paramref name="left" /> and <paramref name="right" /> are equal; otherwise, <see langword="false" />.</returns>
         /// <remarks>Two <see cref="Vector4" /> objects are equal if each element in <paramref name="left" /> is equal to the corresponding element in <paramref name="right" />.</remarks>
+        [Intrinsic]
         [MethodImpl(MethodImplOptions.AggressiveInlining)]
         public static bool operator ==(Vector4 left, Vector4 right) => left.AsVector128() == right.AsVector128();