Update PrimeCalculatorTest.java

exercises/nth-prime/src/test/java/PrimeCalculatorTest.java

@@ -1,5 +1,5 @@
 import org.junit.Before;
-import org.junit.@Ignore("Remove to run test");
+import org.junit.Ignore;
 import org.junit.Rule;
 import org.junit.Test;
 import org.junit.rules.ExpectedException;