test(deps): update dependency io.grpc:protoc-gen-grpc-java to v1.56.1 (#1830)

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This PR contains the following updates:

| Package | Change | Age | Adoption | Passing | Confidence |
|---|---|---|---|---|---|
| [io.grpc:protoc-gen-grpc-java](https://togithub.com/grpc/grpc-java) | `1.56.0` -> `1.56.1` | [![age](https://badges.renovateapi.com/packages/maven/io.grpc:protoc-gen-grpc-java/1.56.1/age-slim)](https://docs.renovatebot.com/merge-confidence/) | [![adoption](https://badges.renovateapi.com/packages/maven/io.grpc:protoc-gen-grpc-java/1.56.1/adoption-slim)](https://docs.renovatebot.com/merge-confidence/) | [![passing](https://badges.renovateapi.com/packages/maven/io.grpc:protoc-gen-grpc-java/1.56.1/compatibility-slim/1.56.0)](https://docs.renovatebot.com/merge-confidence/) | [![confidence](https://badges.renovateapi.com/packages/maven/io.grpc:protoc-gen-grpc-java/1.56.1/confidence-slim/1.56.0)](https://docs.renovatebot.com/merge-confidence/) |

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### Release Notes

<details>
<summary>grpc/grpc-java (io.grpc:protoc-gen-grpc-java)</summary>

### [`v1.56.1`](https://togithub.com/grpc/grpc-java/releases/tag/v1.56.1)

##### Bug fixes

-   core: Fix regression where polling NameResolvers would not refresh after a resolution error ([#&#8203;10328](https://togithub.com/grpc/grpc-java/issues/10328)). The symptom is a transient failure like "UNAVAILABLE: Unable to resolve host" continuing potentially forever. This did not impact DnsNameResolver, but it did impacted GrpclbNameResolver which is the dns name resolver used when `grpc-grpclb` is in the classpath. So even users that think "I don't use grpclb" may have been impacted. `round_robin` is mainly impacted on startup, but if the error happened afterward it would commonly fix itself for short transient DNS failures. `pick_first` is impacted at all times; any failed DNS resolution could cause all future RPCs on the channel to fail.

</details>

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Author: renovate-bot

google-cloud-bigtable/pom.xml

@@ -38,7 +38,7 @@
     <bigtable.cfe-data-batch-endpoint>batch-bigtable.googleapis.com:443</bigtable.cfe-data-batch-endpoint>
 
     <!-- These are needed to compile the protobuf used by Changestream merging acceptance test. -->
-    <test-protoc-grpc.version>1.56.0</test-protoc-grpc.version>
+    <test-protoc-grpc.version>1.56.1</test-protoc-grpc.version>
     <test-protoc.version>3.23.2</test-protoc.version>
   </properties>