style: fix code formatting in README example

Author: satansin123

lib/node_modules/@stdlib/stats/incr/nanme/README.md

@@ -118,13 +118,13 @@ accumulator = incrnanme();
 
 // For each simulated datum, update the mean error...
 for ( i = 0; i < 100; i++ ) {
-    if( randu() < 0.2 ){
-		v1 = NaN;
+    if ( randu() < 0.2 ) {
+        v1 = NaN;
         v2 = NaN;
-	} else {
-		v1 = ( randu()*100.0 ) - 50.0;
+    } else {
+        v1 = ( randu()*100.0 ) - 50.0;
         v2 = ( randu()*100.0 ) - 50.0;
-	}
+    }
 }
 console.log( accumulator() );
 ```