Remove PMD rule SimplifyBooleanReturns (#481)

Remove from default rule set.
Readability of code tends to be better if this rule is not enforced.

It can be re-activated on project basis by using a custom ruleset,
see configuration parameter pmdRuleset and supply an adapted rule
set similar to rules.xml from this repo.

Signed-off-by: Holger Friedrich <[email protected]>

Author: holgerfriedrich

sat-plugin/src/main/resources/rulesets/pmd/rules.xml

@@ -102,9 +102,6 @@
 	<rule ref="category/java/design.xml/SimplifyBooleanExpressions">
 		<priority>3</priority>
 	</rule>
-	<rule ref="category/java/design.xml/SimplifyBooleanReturns">
-		<priority>3</priority>
-	</rule>
 
 	<!-- See https://pmd.github.io/pmd-6.53.0/pmd_rules_java_performance.html -->
 	<rule ref="category/java/performance.xml/AvoidArrayLoops">