[java] Fix AvoidCatchingGenericException for multi-catch

pmd-java/src/main/resources/category/java/design.xml

@@ -62,7 +62,7 @@ Avoid catching generic exceptions such as NullPointerException, RuntimeException
                 <value>
 <![CDATA[
 //CatchParameter[
-    ClassType[
+    (.|UnionType)/ClassType[
         pmd-java:typeIsExactly('java.lang.NullPointerException') or
         pmd-java:typeIsExactly('java.lang.Exception') or
         pmd-java:typeIsExactly('java.lang.RuntimeException')]

pmd-java/src/test/resources/net/sourceforge/pmd/lang/java/rule/design/xml/AvoidCatchingGenericException.xml

@@ -63,7 +63,7 @@ public class Foo {
 
     <test-code>
         <description>failure case with multi-catch</description>
-        <expected-problems>2</expected-problems>
+        <expected-problems>1</expected-problems>
         <code><![CDATA[
 public class Foo {
     void bar() {