build(deps): update dependency com.google.cloud:google-cloud-shared-config to v1.6.0 (#1397)

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This PR contains the following updates:

| Package | Change | Age | Adoption | Passing | Confidence |
|---|---|---|---|---|---|
| [com.google.cloud:google-cloud-shared-config](https://togithub.com/googleapis/java-shared-config) | `1.5.8` -> `1.6.0` | [![age](https://developer.mend.io/api/mc/badges/age/maven/com.google.cloud:google-cloud-shared-config/1.6.0?slim=true)](https://docs.renovatebot.com/merge-confidence/) | [![adoption](https://developer.mend.io/api/mc/badges/adoption/maven/com.google.cloud:google-cloud-shared-config/1.6.0?slim=true)](https://docs.renovatebot.com/merge-confidence/) | [![passing](https://developer.mend.io/api/mc/badges/compatibility/maven/com.google.cloud:google-cloud-shared-config/1.5.8/1.6.0?slim=true)](https://docs.renovatebot.com/merge-confidence/) | [![confidence](https://developer.mend.io/api/mc/badges/confidence/maven/com.google.cloud:google-cloud-shared-config/1.5.8/1.6.0?slim=true)](https://docs.renovatebot.com/merge-confidence/) |

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### Release Notes

<details>
<summary>googleapis/java-shared-config (com.google.cloud:google-cloud-shared-config)</summary>

### [`v1.6.0`](https://togithub.com/googleapis/java-shared-config/blob/HEAD/CHANGELOG.md#160-2023-10-17)

[Compare Source](https://togithub.com/googleapis/java-shared-config/compare/v1.5.8...v1.6.0)

##### Features

-   Add graal-sdk dependency management to java-shared-config ([#&#8203;683](https://togithub.com/googleapis/java-shared-config/issues/683)) ([5cd1d84](https://togithub.com/googleapis/java-shared-config/commit/5cd1d84bf2d68dbe8f9fa7e02d9065082bd56726))

</details>

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Author: renovate-bot

pom.xml

@@ -14,7 +14,7 @@
   <parent>
     <groupId>com.google.cloud</groupId>
     <artifactId>google-cloud-shared-config</artifactId>
-    <version>1.5.8</version>
+    <version>1.6.0</version>
   </parent>
   <developers>
     <developer>