build(deps): update dependency org.apache.maven.plugins:maven-javadoc-plugin to v3.2.0 (#88)

This PR contains the following updates:

| Package | Update | Change |
|---|---|---|
| org.apache.maven.plugins:maven-javadoc-plugin | minor | `3.1.1` -> `3.2.0` |

---

### Renovate configuration

:date: **Schedule**: At any time (no schedule defined).

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

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

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

---

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

---

This PR has been generated by [WhiteSource Renovate](https://renovate.whitesourcesoftware.com). View repository job log [here](https://app.renovatebot.com/dashboard#googleapis/java-spanner-jdbc).

Author: renovate-bot

pom.xml

@@ -483,7 +483,7 @@
       <plugin>
         <groupId>org.apache.maven.plugins</groupId>
         <artifactId>maven-javadoc-plugin</artifactId>
-        <version>3.1.1</version>
+        <version>3.2.0</version>
         <reportSets>
           <reportSet>
             <id>html</id>