deps: update dependency com.google.api.grpc:proto-google-cloud-pubsub-v1 to v1.102.20 (#1384)

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This PR contains the following updates:

| Package | Change | Age | Adoption | Passing | Confidence |
|---|---|---|---|---|---|
| [com.google.api.grpc:proto-google-cloud-pubsub-v1](https://togithub.com/googleapis/java-pubsub/proto-google-cloud-pubsub-v1) ([source](https://togithub.com/googleapis/java-pubsub)) | `1.102.18` -> `1.102.20` | [![age](https://badges.renovateapi.com/packages/maven/com.google.api.grpc:proto-google-cloud-pubsub-v1/1.102.20/age-slim)](https://docs.renovatebot.com/merge-confidence/) | [![adoption](https://badges.renovateapi.com/packages/maven/com.google.api.grpc:proto-google-cloud-pubsub-v1/1.102.20/adoption-slim)](https://docs.renovatebot.com/merge-confidence/) | [![passing](https://badges.renovateapi.com/packages/maven/com.google.api.grpc:proto-google-cloud-pubsub-v1/1.102.20/compatibility-slim/1.102.18)](https://docs.renovatebot.com/merge-confidence/) | [![confidence](https://badges.renovateapi.com/packages/maven/com.google.api.grpc:proto-google-cloud-pubsub-v1/1.102.20/confidence-slim/1.102.18)](https://docs.renovatebot.com/merge-confidence/) |

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Author: renovate-bot

pom.xml

@@ -157,7 +157,7 @@
       <dependency>
         <groupId>com.google.api.grpc</groupId>
         <artifactId>proto-google-cloud-pubsub-v1</artifactId>
-        <version>1.102.18</version>
+        <version>1.102.20</version>
         <scope>test</scope>
       </dependency>
       <dependency>