build(deps): bump com.gradle:develocity-maven-extension

Bumps com.gradle:develocity-maven-extension from 1.21.5 to 1.21.6.

---
updated-dependencies:
- dependency-name: com.gradle:develocity-maven-extension
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

Signed-off-by: dependabot[bot] <[email protected]>

.mvn/extensions.xml

@@ -2,7 +2,7 @@
     <extension>
         <groupId>com.gradle</groupId>
         <artifactId>develocity-maven-extension</artifactId>
-        <version>1.21.5</version>
+        <version>1.21.6</version>
     </extension>
     <extension>
         <groupId>com.gradle</groupId>