test: fix message

Signed-off-by: Athan <kgryte@gmail.com>

Author: kgryte

lib/node_modules/@stdlib/stats/base/ndarray/stdevch/test/test.js

@@ -132,7 +132,7 @@ tape( 'if provided a correction argument yielding `N-correction` less than or eq
 	correction = scalar2ndarray( 1.0, opts );
 
 	v = stdevch( [ vector( x, 1, 1, 0 ), correction ] );
-	t.strictEqual( isnan( v ), true, 'returns NaN' );
+	t.strictEqual( isnan( v ), true, 'returns expected value' );
 
 	t.end();
 });