Bump plugin.spring from 1.8.22 to 1.9.0 in /whiskers-graalvm

Bumps [plugin.spring](https://github.com/JetBrains/kotlin) from 1.8.22 to 1.9.0.
- [Release notes](https://github.com/JetBrains/kotlin/releases)
- [Changelog](https://github.com/JetBrains/kotlin/blob/master/ChangeLog.md)
- [Commits](https://github.com/JetBrains/kotlin/commits)

---
updated-dependencies:
- dependency-name: plugin.spring
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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

whiskers-graalvm/build.gradle.kts

@@ -6,7 +6,7 @@ plugins {
 //	id("org.springframework.experimental.aot") version "0.12.1"
 	id("org.graalvm.buildtools.native") version "0.9.23"
 	kotlin("jvm") version "1.8.22"
-	kotlin("plugin.spring") version "1.8.22"
+	kotlin("plugin.spring") version "1.9.0"
 }
 
 group = "org.jesperancinha.knative"