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.luxtronikheatpump/src/main/java/org/openhab/binding/luxtronikheatpump/internal/enums/HeatpumpChannel.java

@@ -1410,11 +1410,7 @@ public enum HeatpumpChannel {
 
         int code = visiblity.getCode();
 
-        if (visibilityValues.length < code || visibilityValues[code] == 1) {
-            return true;
-        }
-
-        return false;
+        return (visibilityValues.length < code || visibilityValues[code] == 1);
     }
 
     public static HeatpumpChannel fromString(String heatpumpCommand) throws InvalidChannelException {