Bump maven-compiler-plugin from 3.8.1 to 3.9.0 in /NotificationHubs (#115)

Bumps [maven-compiler-plugin](https://github.com/apache/maven-compiler-plugin) from 3.8.1 to 3.9.0.
- [Release notes](https://github.com/apache/maven-compiler-plugin/releases)
- [Commits](apache/maven-compiler-plugin@maven-compiler-plugin-3.8.1...maven-compiler-plugin-3.9.0)

---
updated-dependencies:
- dependency-name: org.apache.maven.plugins:maven-compiler-plugin
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

Author: dependabot[bot]

NotificationHubs/pom.xml

@@ -124,7 +124,7 @@
       <plugin>
         <groupId>org.apache.maven.plugins</groupId>
         <artifactId>maven-compiler-plugin</artifactId>
-        <version>3.8.1</version>
+        <version>3.9.0</version>
         <configuration>
           <source>8</source>
           <target>8</target>