Java 17 features (itests) (#15583)

- replace Collections by List.of and Set.of
- instanceof
- SAT warnings

Signed-off-by: Holger Friedrich <mail@holger-friedrich.de>

itests/org.openhab.binding.modbus.tests/src/main/java/org/openhab/binding/modbus/tests/AbstractModbusOSGiTest.java

@@ -21,7 +21,6 @@ import static org.mockito.ArgumentMatchers.any;
 import static org.mockito.Mockito.*;
 
 import java.util.ArrayList;
-import java.util.Collections;
 import java.util.Dictionary;
 import java.util.HashMap;
 import java.util.HashSet;
@@ -96,7 +95,7 @@ public abstract class AbstractModbusOSGiTest extends JavaOSGiTest {
 
         @Override
         public Set<@NonNull String> getSubscribedEventTypes() {
-            return Collections.singleton(ItemStateEvent.TYPE);
+            return Set.of(ItemStateEvent.TYPE);
         }
 
         @Override