test: update description

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

Author: kgryte

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

@@ -150,7 +150,7 @@ tape( 'the function supports negative strides', function test( t ) {
 	t.end();
 });
 
-tape( 'if provided a stride equal to 0, the function returns the first element', function test( t ) {
+tape( 'when provided an input ndarray having a stride equal to 0, the function returns the first indexed element', function test( t ) {
 	var x;
 	var v;