fix(deps): update dependency com.google.cloud:google-cloud-monitoring to v3.9.0 (GoogleCloudPlatform#7616)

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This PR contains the following updates:

| Package | Change | Age | Adoption | Passing | Confidence |
|---|---|---|---|---|---|
| [com.google.cloud:google-cloud-monitoring](https://togithub.com/googleapis/google-cloud-java) | `3.2.9` -> `3.9.0` | [![age](https://badges.renovateapi.com/packages/maven/com.google.cloud:google-cloud-monitoring/3.9.0/age-slim)](https://docs.renovatebot.com/merge-confidence/) | [![adoption](https://badges.renovateapi.com/packages/maven/com.google.cloud:google-cloud-monitoring/3.9.0/adoption-slim)](https://docs.renovatebot.com/merge-confidence/) | [![passing](https://badges.renovateapi.com/packages/maven/com.google.cloud:google-cloud-monitoring/3.9.0/compatibility-slim/3.2.9)](https://docs.renovatebot.com/merge-confidence/) | [![confidence](https://badges.renovateapi.com/packages/maven/com.google.cloud:google-cloud-monitoring/3.9.0/confidence-slim/3.2.9)](https://docs.renovatebot.com/merge-confidence/) |

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appengine-java8/bigquery/pom.xml

@@ -57,7 +57,7 @@
     <dependency>
       <groupId>com.google.cloud</groupId>
       <artifactId>google-cloud-monitoring</artifactId>
-      <version>3.2.9</version>
+      <version>3.9.0</version>
     </dependency>
 
     <dependency>