Force Spring Cloud server sample to use current Log4j2 version
The `log4j-spring-cloud-config-sample-server` did not use the Log4j2 parent,
therefore it used a very old 2.13.3 Log4j2 version.
</parent>
<properties>
+ <!-- Overrides version from `spring-boot-dependencies` ancestor -->
+ <log4j2.version>${project.version}</log4j2.version>
<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
<project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
<log4jParentDir>${basedir}/../../..</log4jParentDir>
