Minor cleanup

Author: unp1

key.core/src/main/java/de/uka/ilkd/key/util/HelperClassForTests.java

@@ -3,6 +3,7 @@
  * SPDX-License-Identifier: GPL-2.0-only */
 package de.uka.ilkd.key.util;
 
+import java.lang.reflect.Field;
 import java.nio.file.Path;
 import java.util.HashMap;
 import java.util.Map;
@@ -290,4 +291,10 @@ public static KeYEnvironment<DefaultUserInterfaceControl> createKeYEnvironment()
         return KeYEnvironment.load(DUMMY_KEY_FILE);
     }
 
+    public static Field getPrivateField(Object o, String fieldName) throws NoSuchFieldException {
+        final Field field = o.getClass().getDeclaredField(fieldName);
+        field.setAccessible(true);
+        return field;
+    }
+
 }

key.core/src/test/java/de/uka/ilkd/key/proof/replay/TestCopyingReplayer.java

@@ -13,6 +13,7 @@
 import de.uka.ilkd.key.proof.Counter;
 import de.uka.ilkd.key.proof.Proof;
 import de.uka.ilkd.key.settings.GeneralSettings;
+import de.uka.ilkd.key.util.HelperClassForTests;
 
 import org.key_project.util.helper.FindResources;
 
@@ -40,8 +41,8 @@ public void resetCounters(Proof proof) {
         }
 
         try {
-            final Field countersField = proof.getServices().getClass().getDeclaredField("counters");
-            countersField.setAccessible(true);
+            final Field countersField =
+                HelperClassForTests.getPrivateField(proof.getServices(), "counters");
             // noinspection unchecked
             ((HashMap<String, Counter>) countersField.get(proof.getServices())).clear();
         } catch (NoSuchFieldException | IllegalAccessException e) {