chore(deps): update dependency com.google.cloud:google-cloud-spanner-jdbc to v2.7.9 (#1007)

[![Mend Renovate](https://app.renovatebot.com/images/banner.svg)](https://renovatebot.com)

This PR contains the following updates:

| Package | Change | Age | Adoption | Passing | Confidence |
|---|---|---|---|---|---|
| [com.google.cloud:google-cloud-spanner-jdbc](https://togithub.com/googleapis/java-spanner-jdbc) | `2.7.8` -> `2.7.9` | [![age](https://badges.renovateapi.com/packages/maven/com.google.cloud:google-cloud-spanner-jdbc/2.7.9/age-slim)](https://docs.renovatebot.com/merge-confidence/) | [![adoption](https://badges.renovateapi.com/packages/maven/com.google.cloud:google-cloud-spanner-jdbc/2.7.9/adoption-slim)](https://docs.renovatebot.com/merge-confidence/) | [![passing](https://badges.renovateapi.com/packages/maven/com.google.cloud:google-cloud-spanner-jdbc/2.7.9/compatibility-slim/2.7.8)](https://docs.renovatebot.com/merge-confidence/) | [![confidence](https://badges.renovateapi.com/packages/maven/com.google.cloud:google-cloud-spanner-jdbc/2.7.9/confidence-slim/2.7.8)](https://docs.renovatebot.com/merge-confidence/) |

---

### Release Notes

<details>
<summary>googleapis/java-spanner-jdbc</summary>

### [`v2.7.9`](https://togithub.com/googleapis/java-spanner-jdbc/blob/HEAD/CHANGELOG.md#&#8203;279-httpsgithubcomgoogleapisjava-spanner-jdbccomparev278v279-2022-10-06)

[Compare Source](https://togithub.com/googleapis/java-spanner-jdbc/compare/v2.7.8...v2.7.9)

##### Dependencies

-   Update dependency com.google.cloud:google-cloud-spanner-bom to v6.31.2 ([#&#8203;1002](https://togithub.com/googleapis/java-spanner-jdbc/issues/1002)) ([f2ac8e3](https://togithub.com/googleapis/java-spanner-jdbc/commit/f2ac8e392e972d326bc5702855385471febea87c))

</details>

---

### Configuration

📅 **Schedule**: Branch creation - At any time (no schedule defined), Automerge - At any time (no schedule defined).

🚦 **Automerge**: Disabled by config. Please merge this manually once you are satisfied.

♻ **Rebasing**: Whenever PR becomes conflicted, or you tick the rebase/retry checkbox.

🔕 **Ignore**: Close this PR and you won't be reminded about this update again.

---

 - [ ] <!-- rebase-check -->If you want to rebase/retry this PR, click this checkbox.

---

This PR has been generated by [Mend Renovate](https://www.mend.io/free-developer-tools/renovate/). View repository job log [here](https://app.renovatebot.com/dashboard#github/googleapis/java-spanner-jdbc).
<!--renovate-debug:eyJjcmVhdGVkSW5WZXIiOiIzMi4yMTkuMSIsInVwZGF0ZWRJblZlciI6IjMyLjIxOS4xIn0=-->

Author: renovate-bot

samples/install-without-bom/pom.xml

@@ -29,7 +29,7 @@
     <dependency>
       <groupId>com.google.cloud</groupId>
       <artifactId>google-cloud-spanner-jdbc</artifactId>
-      <version>2.7.8</version>
+      <version>2.7.9</version>
     </dependency>
     <!-- [END spanner-jdbc_install_without_bom] -->