fix comment spelling

h2/src/main/org/h2/engine/Session.java

@@ -656,7 +656,7 @@ public class Session extends SessionWithState {
         }
         if (locks.size() > 0) {
             synchronized (database) {
-                // don't use the enhance for loop to safe memory
+                // don't use the enhanced for loop to save memory
                 for (int i = 0, size = locks.size(); i < size; i++) {
                     Table t = locks.get(i);
                     t.unlock(this);