Fix issue ID

Author: vy

src/changelog/.2.x.x/3211_fix_JTL_StackTraceStringResolver.xml renamed to src/changelog/.2.x.x/3212_fix_JTL_StackTraceStringResolver.xml

@@ -3,6 +3,6 @@
        xmlns="https://logging.apache.org/xml/ns"
        xsi:schemaLocation="https://logging.apache.org/xml/ns https://logging.apache.org/xml/ns/log4j-changelog-0.xsd"
        type="fixed">
-  <issue id="3211" link="https://github.com/apache/logging-log4j2/pull/3211"/>
+  <issue id="3212" link="https://github.com/apache/logging-log4j2/pull/3212"/>
   <description format="asciidoc">Fix `ArrayIndexOutOfBoundsException` in JSON Template Layout truncated exception resolver</description>
 </entry>