test(deps): update dependency com.google.protobuf:protoc to v3.25.4 (#2290)

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This PR contains the following updates:

| Package | Change | Age | Adoption | Passing | Confidence |
|---|---|---|---|---|---|
| [com.google.protobuf:protoc](https://developers.google.com/protocol-buffers/) ([source](https://togithub.com/protocolbuffers/protobuf)) | `3.25.3` -> `3.25.4` | [![age](https://developer.mend.io/api/mc/badges/age/maven/com.google.protobuf:protoc/3.25.4?slim=true)](https://docs.renovatebot.com/merge-confidence/) | [![adoption](https://developer.mend.io/api/mc/badges/adoption/maven/com.google.protobuf:protoc/3.25.4?slim=true)](https://docs.renovatebot.com/merge-confidence/) | [![passing](https://developer.mend.io/api/mc/badges/compatibility/maven/com.google.protobuf:protoc/3.25.3/3.25.4?slim=true)](https://docs.renovatebot.com/merge-confidence/) | [![confidence](https://developer.mend.io/api/mc/badges/confidence/maven/com.google.protobuf:protoc/3.25.3/3.25.4?slim=true)](https://docs.renovatebot.com/merge-confidence/) |

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### Release Notes

<details>
<summary>protocolbuffers/protobuf (com.google.protobuf:protoc)</summary>

### [`v3.25.4`](https://togithub.com/protocolbuffers/protobuf/compare/v3.25.3...v3.25.4)

</details>

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Author: renovate-bot

google-cloud-bigtable/pom.xml

@@ -44,7 +44,7 @@
 
     <!-- These are needed to compile the protobuf used by Changestream merging acceptance test. -->
     <test-protoc-grpc.version>1.65.0</test-protoc-grpc.version>
-    <test-protoc.version>3.25.3</test-protoc.version>
+    <test-protoc.version>3.25.4</test-protoc.version>
   </properties>
 
   <dependencyManagement>