build(deps): bump fmt-maven-plugin from 2.6.0 to 2.9

Bumps [fmt-maven-plugin](https://github.com/coveo/fmt-maven-plugin) from 2.6.0 to 2.9.
- [Release notes](https://github.com/coveo/fmt-maven-plugin/releases)
- [Commits](spotify/fmt-maven-plugin@2.6.0...2.9.0)

Author: dependabot-preview[bot]

pom.xml

@@ -278,7 +278,7 @@
             <plugin>
                 <groupId>com.coveo</groupId>
                 <artifactId>fmt-maven-plugin</artifactId>
-                <version>2.6.0</version>
+                <version>2.9</version>
                 <executions>
                     <execution>
                         <goals>