chore(deps): update dependency com.diffplug.spotless:spotless-maven-plugin to v3.1.0 (#1692)

This PR contains the following updates:

| Package | Change | Age | Confidence |
|---|---|---|---|
|
[com.diffplug.spotless:spotless-maven-plugin](https://redirect.github.com/diffplug/spotless)
| `3.0.0` -> `3.1.0` |
[![age](https://developer.mend.io/api/mc/badges/age/maven/com.diffplug.spotless:spotless-maven-plugin/3.1.0?slim=true)](https://docs.renovatebot.com/merge-confidence/)
|
[![confidence](https://developer.mend.io/api/mc/badges/confidence/maven/com.diffplug.spotless:spotless-maven-plugin/3.0.0/3.1.0?slim=true)](https://docs.renovatebot.com/merge-confidence/)
|

---

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> Some dependencies could not be looked up. Check the Dependency
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---

### Release Notes

<details>
<summary>diffplug/spotless
(com.diffplug.spotless:spotless-maven-plugin)</summary>

###
[`v3.1.0`](https://redirect.github.com/diffplug/spotless/blob/HEAD/CHANGES.md#310---2025-02-20)

##### Added

- Support for`clang-format` on maven-plugin
([#&#8203;2406](https://redirect.github.com/diffplug/spotless/pull/2406))
- Allow overriding classLoader for all `JarState`s to enable
spotless-cli
([#&#8203;2427](https://redirect.github.com/diffplug/spotless/pull/2427))

</details>

---

### Configuration

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rebase/retry checkbox.

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---

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integration-tests/it-spring-boot-smoke-test/pom.xml

@@ -147,7 +147,7 @@
       <plugin>
         <groupId>com.diffplug.spotless</groupId>
         <artifactId>spotless-maven-plugin</artifactId>
-        <version>3.0.0</version>
+        <version>3.1.0</version>
         <configuration>
           <java>
             <googleJavaFormat/>

prometheus-metrics-parent/pom.xml

@@ -71,7 +71,7 @@
       <plugin>
         <groupId>com.diffplug.spotless</groupId>
         <artifactId>spotless-maven-plugin</artifactId>
-        <version>3.0.0</version>
+        <version>3.1.0</version>
         <configuration>
           <java>
             <googleJavaFormat/>