deps: update dependency com.google.protobuf:protobuf-java to v3.21.9 (#3831)

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This PR contains the following updates:

| Package | Change | Age | Adoption | Passing | Confidence |
|---|---|---|---|---|---|
| [com.google.protobuf:protobuf-java](https://developers.google.com/protocol-buffers/) ([source](https://togithub.com/protocolbuffers/protobuf)) | `3.21.8` -> `3.21.9` | [![age](https://badges.renovateapi.com/packages/maven/com.google.protobuf:protobuf-java/3.21.9/age-slim)](https://docs.renovatebot.com/merge-confidence/) | [![adoption](https://badges.renovateapi.com/packages/maven/com.google.protobuf:protobuf-java/3.21.9/adoption-slim)](https://docs.renovatebot.com/merge-confidence/) | [![passing](https://badges.renovateapi.com/packages/maven/com.google.protobuf:protobuf-java/3.21.9/compatibility-slim/3.21.8)](https://docs.renovatebot.com/merge-confidence/) | [![confidence](https://badges.renovateapi.com/packages/maven/com.google.protobuf:protobuf-java/3.21.9/confidence-slim/3.21.8)](https://docs.renovatebot.com/merge-confidence/) |

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### Release Notes

<details>
<summary>protocolbuffers/protobuf</summary>

### [`v3.21.9`](https://togithub.com/protocolbuffers/protobuf/compare/v3.21.8...v3.21.9)

[Compare Source](https://togithub.com/protocolbuffers/protobuf/compare/v3.21.8...v3.21.9)

</details>

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Author: renovate-bot

hbase-migration-tools/mirroring-client/bigtable-hbase-mirroring-client-1.x-parent/bigtable-hbase-mirroring-client-1.x-integration-tests/pom.xml

@@ -249,7 +249,7 @@ limitations under the License.
     <dependency>
       <groupId>com.google.protobuf</groupId>
       <artifactId>protobuf-java</artifactId>
-      <version>3.21.8</version>
+      <version>3.21.9</version>
       <scope>test</scope>
     </dependency>