Remove commented out code.

The block:

if (isPrime(n)) return n;

is already executed with the same value n in lines above.
diff --git a/commons-numbers-primes/src/main/java/org/apache/commons/numbers/primes/Primes.java b/commons-numbers-primes/src/main/java/org/apache/commons/numbers/primes/Primes.java
index 5c3ad73..b135f4b 100644
--- a/commons-numbers-primes/src/main/java/org/apache/commons/numbers/primes/Primes.java
+++ b/commons-numbers-primes/src/main/java/org/apache/commons/numbers/primes/Primes.java
@@ -88,7 +88,6 @@
         if (0 == rem) { // if n % 3 == 0
             n += 2; // n % 3 == 2
         } else if (1 == rem) { // if n % 3 == 1
-            // if (isPrime(n)) return n;
             n += 4; // n % 3 == 2
         }
         while (true) { // this loop skips all multiple of 3