build(deps): Bump io.kubernetes:client-java from 18.0.1 to 20.0.1-legacy

Bumps [io.kubernetes:client-java](https://github.com/kubernetes-client/java) from 18.0.1 to 20.0.1-legacy.
- [Release notes](https://github.com/kubernetes-client/java/releases)
- [Changelog](https://github.com/kubernetes-client/java/blob/master/CHANGELOG.md)
- [Commits](kubernetes-client/java@v18.0.1...v20.0.1-legacy)

---
updated-dependencies:
- dependency-name: io.kubernetes:client-java
  dependency-type: direct:production
  update-type: version-update:semver-major
...

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

build.gradle.kts

@@ -24,7 +24,7 @@ repositories {
 
 // Dependencies are managed with Gradle version catalog - read more: https://docs.gradle.org/current/userguide/platforms.html#sub:version-catalog
 dependencies {
-    implementation("io.kubernetes:client-java:18.0.1")
+    implementation("io.kubernetes:client-java:20.0.1-legacy")
 }
 
 // Set the JVM language level used to build the project. Use Java 11 for 2020.3+, and Java 17 for 2022.2+.