chore(deps): update dependency com.google.cloud:google-cloud-datastore to v2.21.3 (#1572)

This PR contains the following updates:

| Package | Change | Age | Adoption | Passing | Confidence |
|---|---|---|---|---|---|
| [com.google.cloud:google-cloud-datastore](https://redirect.github.com/googleapis/java-datastore) | `2.21.2` -> `2.21.3` | [![age](https://developer.mend.io/api/mc/badges/age/maven/com.google.cloud:google-cloud-datastore/2.21.3?slim=true)](https://docs.renovatebot.com/merge-confidence/) | [![adoption](https://developer.mend.io/api/mc/badges/adoption/maven/com.google.cloud:google-cloud-datastore/2.21.3?slim=true)](https://docs.renovatebot.com/merge-confidence/) | [![passing](https://developer.mend.io/api/mc/badges/compatibility/maven/com.google.cloud:google-cloud-datastore/2.21.2/2.21.3?slim=true)](https://docs.renovatebot.com/merge-confidence/) | [![confidence](https://developer.mend.io/api/mc/badges/confidence/maven/com.google.cloud:google-cloud-datastore/2.21.2/2.21.3?slim=true)](https://docs.renovatebot.com/merge-confidence/) |

---

### Release Notes

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

### [`v2.21.3`](https://redirect.github.com/googleapis/java-datastore/blob/HEAD/CHANGELOG.md#2213-2024-09-11)

[Compare Source](https://redirect.github.com/googleapis/java-datastore/compare/v2.21.2...v2.21.3)

##### Dependencies

-   Update dependency com.google.cloud:sdk-platform-java-config to v3.35.0 ([#&#8203;1561](https://redirect.github.com/googleapis/java-datastore/issues/1561)) ([5a79fd8](https://redirect.github.com/googleapis/java-datastore/commit/5a79fd8d1202e65c02423fe40402c41af6050efa))
-   Update dependency com.google.errorprone:error_prone_core to v2.31.0 ([#&#8203;1523](https://redirect.github.com/googleapis/java-datastore/issues/1523)) ([8d3af32](https://redirect.github.com/googleapis/java-datastore/commit/8d3af322fb56032cd7a9d29e60fd93d1f3e7e632))
-   Update dependency com.google.guava:guava-testlib to v33.3.0-jre ([#&#8203;1548](https://redirect.github.com/googleapis/java-datastore/issues/1548)) ([18ba37f](https://redirect.github.com/googleapis/java-datastore/commit/18ba37f60b5b3e69c95f6e55a28daf8c0de82ba9))
-   Update dependency org.easymock:easymock to v5.4.0 ([#&#8203;1482](https://redirect.github.com/googleapis/java-datastore/issues/1482)) ([ee788a1](https://redirect.github.com/googleapis/java-datastore/commit/ee788a162841994e09a61bb81b94cbe93353a78e))

</details>

---

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Author: renovate-bot

samples/install-without-bom/pom.xml

@@ -29,7 +29,7 @@
     <dependency>
       <groupId>com.google.cloud</groupId>
       <artifactId>google-cloud-datastore</artifactId>
-      <version>2.21.2</version>
+      <version>2.21.3</version>
     </dependency>
     <!-- [END datastore_install_without_bom] -->