Clean up Besu runtime files when stopping ATs

Signed-off-by: Fabio Di Fabio <fabio.difabio@consensys.net>

Author: fab-10

acceptance-tests/dsl/src/main/java/org/hyperledger/besu/tests/acceptance/dsl/node/BesuNode.java

@@ -786,6 +786,21 @@ public void stop() {
       nodeRequests.shutdown();
       nodeRequests = null;
     }
+
+    deleteRuntimeFiles();
+  }
+
+  private void deleteRuntimeFiles() {
+    try {
+      Files.deleteIfExists(homeDirectory.resolve("besu.networks"));
+    } catch (IOException e) {
+      LOG.error("Failed to clean up besu.networks file in {}", homeDirectory, e);
+    }
+    try {
+      Files.deleteIfExists(homeDirectory.resolve("besu.ports"));
+    } catch (IOException e) {
+      LOG.error("Failed to clean up besu.ports file in {}", homeDirectory, e);
+    }
   }
 
   @Override