Update the max ULP for log from 3 to 1 for the C reference test.
diff --git a/commons-numbers-complex/src/test/java/org/apache/commons/numbers/complex/CReferenceTest.java b/commons-numbers-complex/src/test/java/org/apache/commons/numbers/complex/CReferenceTest.java
index 38090c1..3b02907 100644
--- a/commons-numbers-complex/src/test/java/org/apache/commons/numbers/complex/CReferenceTest.java
+++ b/commons-numbers-complex/src/test/java/org/apache/commons/numbers/complex/CReferenceTest.java
@@ -312,7 +312,7 @@
 
     @Test
     public void testLog() {
-        assertOperation("log", Complex::log, 3);
+        assertOperation("log", Complex::log, 1);
     }
 
     @Test