Bump maven-compiler-plugin in /plugins/maven/example-server (#1107)

Bumps [maven-compiler-plugin](https://github.com/apache/maven-compiler-plugin) from 3.8.1 to 3.11.0.
- [Release notes](https://github.com/apache/maven-compiler-plugin/releases)
- [Commits](https://github.com/apache/maven-compiler-plugin/compare/maven-compiler-plugin-3.8.1...maven-compiler-plugin-3.11.0)

---
updated-dependencies:
- dependency-name: org.apache.maven.plugins:maven-compiler-plugin
  dependency-type: direct:production
  update-type: version-update:semver-minor
...
Signed-off-by: Ndependabot[bot] <support@github.com>
Co-authored-by: Ndependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

plugins/maven/example-server/pom.xml

@@ -49,7 +49,7 @@
             <plugin>
                 <groupId>org.apache.maven.plugins</groupId>
                 <artifactId>maven-compiler-plugin</artifactId>
-                <version>3.8.1</version>
+                <version>3.11.0</version>
                 <configuration>
                     <encoding>UTF-8</encoding>
                     <source>1.8</source>