chore(deps): update dependency org.junit:junit-bom to v5.9.0 (googleapis#954)

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This PR contains the following updates:

| Package | Change | Age | Adoption | Passing | Confidence |
|---|---|---|---|---|---|
| [org.junit:junit-bom](https://junit.org/junit5/) ([source](https://github.com/junit-team/junit5)) | `5.8.2` -> `5.9.0` | [![age](https://badges.renovateapi.com/packages/maven/org.junit:junit-bom/5.9.0/age-slim)](https://docs.renovatebot.com/merge-confidence/) | [![adoption](https://badges.renovateapi.com/packages/maven/org.junit:junit-bom/5.9.0/adoption-slim)](https://docs.renovatebot.com/merge-confidence/) | [![passing](https://badges.renovateapi.com/packages/maven/org.junit:junit-bom/5.9.0/compatibility-slim/5.8.2)](https://docs.renovatebot.com/merge-confidence/) | [![confidence](https://badges.renovateapi.com/packages/maven/org.junit:junit-bom/5.9.0/confidence-slim/5.8.2)](https://docs.renovatebot.com/merge-confidence/) |

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pom.xml

@@ -60,7 +60,7 @@
   <properties>
     <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
     <project.google.http.version>1.42.2</project.google.http.version>
-    <project.junit.bom.version>5.8.2</project.junit.bom.version>
+    <project.junit.bom.version>5.9.0</project.junit.bom.version>
     <project.guava.version>31.0.1-android</project.guava.version>
     <project.appengine.version>2.0.5</project.appengine.version>
     <project.findbugs.version>3.0.2</project.findbugs.version>