deps: update dependency com.google.cloud:google-cloud-spanner to v6.105.0 (googleapis#2325)

This PR contains the following updates:

| Package | Change | [Age](https://docs.renovatebot.com/merge-confidence/) | [Adoption](https://docs.renovatebot.com/merge-confidence/) | [Passing](https://docs.renovatebot.com/merge-confidence/) | [Confidence](https://docs.renovatebot.com/merge-confidence/) |
|---|---|---|---|---|---|
| [com.google.cloud:google-cloud-spanner](https://redirect.github.com/googleapis/java-spanner) | `6.104.0` -> `6.105.0` | ![age](https://developer.mend.io/api/mc/badges/age/maven/com.google.cloud:google-cloud-spanner/6.105.0?slim=true) | ![adoption](https://developer.mend.io/api/mc/badges/adoption/maven/com.google.cloud:google-cloud-spanner/6.105.0?slim=true) | ![passing](https://developer.mend.io/api/mc/badges/compatibility/maven/com.google.cloud:google-cloud-spanner/6.104.0/6.105.0?slim=true) | ![confidence](https://developer.mend.io/api/mc/badges/confidence/maven/com.google.cloud:google-cloud-spanner/6.104.0/6.105.0?slim=true) |

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### Release Notes

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

### [`v6.105.0`](https://redirect.github.com/googleapis/java-spanner/blob/HEAD/CHANGELOG.md#61050-2025-12-16)

[Compare Source](https://redirect.github.com/googleapis/java-spanner/compare/v6.104.0...v6.105.0)

##### Features

- Add support of dynamic channel pooling ([#&googleapis#8203;4265](https://redirect.github.com/googleapis/java-spanner/issues/4265)) ([923a14a](https://redirect.github.com/googleapis/java-spanner/commit/923a14aad99ff6fc91868f02d657145dd0f31c18))
- Include RequestID in requests and errors ([#&googleapis#8203;4263](https://redirect.github.com/googleapis/java-spanner/issues/4263)) ([afd7d6b](https://redirect.github.com/googleapis/java-spanner/commit/afd7d6b008f13d7a4d1a3b7f924122bd41d14b59))
- Make grpc-gcp default enabled ([#&googleapis#8203;4239](https://redirect.github.com/googleapis/java-spanner/issues/4239)) ([bb82f9e](https://redirect.github.com/googleapis/java-spanner/commit/bb82f9e55c40cac29b090e54be780c2e42545ee1))

##### Bug Fixes

- Refine connecitivity metrics to capture RPCs with no response he… ([#&googleapis#8203;4252](https://redirect.github.com/googleapis/java-spanner/issues/4252)) ([7b49412](https://redirect.github.com/googleapis/java-spanner/commit/7b4941221969f48d077ff459214c7d1e65ef843c))
- Retry as PDML dit not retry Resource limit exceeded ([#&googleapis#8203;4258](https://redirect.github.com/googleapis/java-spanner/issues/4258)) ([c735d42](https://redirect.github.com/googleapis/java-spanner/commit/c735d42875092b0d1482fe641b99645f288cdf4f)), closes [#&googleapis#8203;4253](https://redirect.github.com/googleapis/java-spanner/issues/4253)

##### Dependencies

- Update dependency com.google.cloud:sdk-platform-java-config to v3.54.2 ([#&googleapis#8203;4261](https://redirect.github.com/googleapis/java-spanner/issues/4261)) ([61dfd62](https://redirect.github.com/googleapis/java-spanner/commit/61dfd620637da6ef76b699edbad1095c26b81950))
- Update googleapis/sdk-platform-java action to v2.64.2 ([#&googleapis#8203;4262](https://redirect.github.com/googleapis/java-spanner/issues/4262)) ([f9505a9](https://redirect.github.com/googleapis/java-spanner/commit/f9505a97bdd9f6da7dd5ab1b60b47f7ed0a70402))

</details>

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Author: renovate-bot

java-spanner-jdbc/samples/spring-data-mybatis/googlesql/pom.xml

@@ -94,7 +94,7 @@
     <dependency>
       <groupId>com.google.cloud</groupId>
       <artifactId>google-cloud-spanner</artifactId>
-      <version>6.104.0</version>
+      <version>6.105.0</version>
       <type>test-jar</type>
       <scope>test</scope>
     </dependency>