Make "reduction types" list normative

The "reduction types" list was styled as a non-normative note. The
element-wise ops (add, equal, abs, etc.) don't do this. Be consistent
here.

index.bs

@@ -4975,7 +4975,7 @@ partial interface MLGraphBuilder {
     **Returns:** an {{MLOperand}}. The reduced output tensor. If the input operand is a scalar, the reduction function is applied to the scalar value and the output is also a scalar.
 </div>
 
-<div class="note">
+<div>
     **Reduction types:**
         - *L1*: Compute the <a href="https://mathworld.wolfram.com/L1-Norm.html">L1 norm</a>, the sum of the absolute value of all the input values.
         - *L2*: Compute the <a href="https://mathworld.wolfram.com/L2-Norm.html">L2 norm</a>, the square root of the sum of the square of all the input values.