fix: update isnan checks to use appropriate parameters

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Author: anandkaranubc

lib/node_modules/@stdlib/stats/base/dists/arcsine/ctor/benchmark/benchmark.js

@@ -112,7 +112,7 @@ bench( pkg+'::set:a', function benchmark( bm ) {
 		}
 	}
 	bm.toc();
-	if ( isnan( y ) ) {
+	if ( isnan( dist.a ) ) {
 		bm.fail( 'should not return NaN' );
 	}
 	bm.pass( 'benchmark finished' );
@@ -170,7 +170,7 @@ bench( pkg+'::set:b', function benchmark( bm ) {
 		}
 	}
 	bm.toc();
-	if ( isnan( y ) ) {
+	if ( isnan( dist.b ) ) {
 		bm.fail( 'should not return NaN' );
 	}
 	bm.pass( 'benchmark finished' );