[doc] Update release notes (#4483)

Closes #4483

docs/pages/release_notes.md

@@ -372,6 +372,7 @@ Language specific fixes:
     * [#2537](https://github.com/pmd/pmd/issues/2537): \[java] DontCallThreadRun can't detect the case that call run() in `this.run()`
     * [#2538](https://github.com/pmd/pmd/issues/2538): \[java] DontCallThreadRun can't detect the case that call run() in `foo.bar.run()`
     * [#2577](https://github.com/pmd/pmd/issues/2577): \[java] UseNotifyAllInsteadOfNotify falsely detect a special case with argument: `foo.notify(bar)`
+    * [#4483](https://github.com/pmd/pmd/issues/4483): \[java] NonThreadSafeSingleton false positive with double-checked locking
 * java-performance
     * [#1224](https://github.com/pmd/pmd/issues/1224): \[java] InefficientEmptyStringCheck false negative in anonymous class
     * [#2587](https://github.com/pmd/pmd/issues/2587): \[java] AvoidArrayLoops could also check for list copy through iterated List.add()

pmd-java/src/test/resources/net/sourceforge/pmd/lang/java/rule/multithreading/xml/NonThreadSafeSingleton.xml

@@ -176,7 +176,7 @@ class A extends B {
     </test-code>
 
     <test-code>
-        <description>False positive with correct double checked pattern</description>
+        <description>False positive with correct double-checked pattern #4483</description>
         <expected-problems>0</expected-problems>
         <code><![CDATA[
 public class Foo {