Bump log4j2.version from 2.8.2 to 2.13.3 in /sample

Bumps `log4j2.version` from 2.8.2 to 2.13.3.

Updates `log4j-slf4j-impl` from 2.8.2 to 2.13.3

Updates `log4j-core` from 2.8.2 to 2.13.3

Signed-off-by: dependabot[bot] <support@github.com>

Author: dependabot[bot]

sample/pom.xml

@@ -12,7 +12,7 @@
 
     <properties>
         <tomcat.version>8.0.39</tomcat.version>
-        <log4j2.version>2.8.2</log4j2.version>
+        <log4j2.version>2.13.3</log4j2.version>
         <logback.version>1.1.3</logback.version>
         <jackson.version>2.5.4</jackson.version>
         <slf4j.version>1.7.12</slf4j.version>