Fix SAT warnings (#14202)

* Fix SAT warnings

- checkstyle.ModifierOrderCheck
- checkstyle.OneStatementPerLineCheck
- checkstyle.NeedBracesCheck
- PMD.UseStandardCharsets
- PMD.UseCollectionIsEmpty
- PMD.UnusedLocalVariable
- PMD.SimplifyBooleanReturns where reasonable, suppress where
readability is better without change
- PMD.SimplifyBooleanExpressions

* Include StandardCharsets

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

bundles/org.openhab.binding.nanoleaf/src/main/java/org/openhab/binding/nanoleaf/internal/handler/NanoleafControllerHandler.java

@@ -903,8 +903,6 @@ public class NanoleafControllerHandler extends BaseBridgeHandler implements Nano
                 break;
             case CHANNEL_COLOR_TEMPERATURE_ABS:
                 // Color temperature (absolute)
-                int colorTempKelvin;
-
                 IntegerState state = new Ct();
                 if (command instanceof DecimalType) {
                     state.setValue(((DecimalType) command).intValue());

bundles/org.openhab.binding.nanoleaf/src/main/java/org/openhab/binding/nanoleaf/internal/model/PanelLayout.java

@@ -78,7 +78,7 @@ public class PanelLayout {
             goEquals = go.equals(otherGo);
         }
 
-        if (goEquals == false) {
+        if (!goEquals) {
             // No reason to compare layout if global oriantation is different
             return false;
         }