chore(deps): update dependency org.apache.maven.plugins:maven-compiler-plugin to v3.9.0 (#1955)

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This PR contains the following updates:

| Package | Change | Age | Adoption | Passing | Confidence |
|---|---|---|---|---|---|
| [org.apache.maven.plugins:maven-compiler-plugin](https://maven.apache.org/plugins/) ([source](https://togithub.com/apache/maven-compiler-plugin)) | `3.8.1` -> `3.9.0` | [![age](https://badges.renovateapi.com/packages/maven/org.apache.maven.plugins:maven-compiler-plugin/3.9.0/age-slim)](https://docs.renovatebot.com/merge-confidence/) | [![adoption](https://badges.renovateapi.com/packages/maven/org.apache.maven.plugins:maven-compiler-plugin/3.9.0/adoption-slim)](https://docs.renovatebot.com/merge-confidence/) | [![passing](https://badges.renovateapi.com/packages/maven/org.apache.maven.plugins:maven-compiler-plugin/3.9.0/compatibility-slim/3.8.1)](https://docs.renovatebot.com/merge-confidence/) | [![confidence](https://badges.renovateapi.com/packages/maven/org.apache.maven.plugins:maven-compiler-plugin/3.9.0/confidence-slim/3.8.1)](https://docs.renovatebot.com/merge-confidence/) |

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Author: renovate-bot

pom.xml

@@ -241,7 +241,7 @@
         </plugin>
         <plugin>
           <artifactId>maven-compiler-plugin</artifactId>
-          <version>3.8.1</version>
+          <version>3.9.0</version>
           <configuration>
             <source>1.7</source>
             <target>1.7</target>