deps: update dependency io.grpc:grpc-bom to v1.48.0 (#752)

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This PR contains the following updates:

| Package | Change | Age | Adoption | Passing | Confidence |
|---|---|---|---|---|---|
| [io.grpc:grpc-bom](https://github.com/grpc/grpc-java) | `1.47.0` -> `1.48.0` | [![age](https://badges.renovateapi.com/packages/maven/io.grpc:grpc-bom/1.48.0/age-slim)](https://docs.renovatebot.com/merge-confidence/) | [![adoption](https://badges.renovateapi.com/packages/maven/io.grpc:grpc-bom/1.48.0/adoption-slim)](https://docs.renovatebot.com/merge-confidence/) | [![passing](https://badges.renovateapi.com/packages/maven/io.grpc:grpc-bom/1.48.0/compatibility-slim/1.47.0)](https://docs.renovatebot.com/merge-confidence/) | [![confidence](https://badges.renovateapi.com/packages/maven/io.grpc:grpc-bom/1.48.0/confidence-slim/1.47.0)](https://docs.renovatebot.com/merge-confidence/) |

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### Release Notes

<details>
<summary>grpc/grpc-java</summary>

### [`v1.48.0`](https://github.com/grpc/grpc-java/compare/v1.47.0...v1.48.0)

[Compare Source](https://github.com/grpc/grpc-java/compare/v1.47.0...v1.48.0)

</details>

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first-party-dependencies/pom.xml

@@ -55,7 +55,7 @@
   <properties>
     <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
     <site.installationModule>${project.artifactId}</site.installationModule>
-    <grpc.version>1.47.0</grpc.version>
+    <grpc.version>1.48.0</grpc.version>
     <gax.version>2.18.4</gax.version>
     <grpc-gcp.version>1.2.1</grpc-gcp.version>
     <guava.version>31.1-jre</guava.version>