Fix: Replace deprecated OpenJDK Docker images with Eclipse Temurin

## Problem
The official OpenJDK Docker images have been deprecated and removed from
Docker Hub by Oracle, causing test failures with the error:
"manifest for openjdk:*-jdk-slim not found: manifest unknown"

This issue affected all Kotlin test suites that relied on OpenJDK 8, 11, and 17.

## Solution
Replaced all deprecated OpenJDK images with Eclipse Temurin images:
- `openjdk:8-jdk-slim` → `eclipse-temurin:8-jdk-jammy`
- `openjdk:11-jdk-slim` → `eclipse-temurin:11-jdk-jammy`
- `openjdk:17-jdk-slim` → `eclipse-temurin:17-jdk-jammy`

## Background
Eclipse Temurin is now the official OpenJDK distribution maintained by the
Eclipse Foundation and the Adoptium Working Group. It provides fully
compatible, drop-in replacement images for the deprecated OpenJDK images.

The `-jammy` variant is based on Ubuntu 22.04 LTS and provides a similar
environment to the previous `-slim` images.

## References
- https://hub.docker.com/_/eclipse-temurin
- https://adoptium.net/

## Files Changed
- tests/KotlinJava8Test.php
- tests/KotlinJava11Test.php
- tests/KotlinJava17Test.php

Author: ChiragAgg5k

tests/KotlinJava11Test.php

@@ -17,7 +17,7 @@ class KotlinJava11Test extends Base
         'chmod +x tests/sdks/kotlin/gradlew',
     ];
     protected string $command =
-        'docker run --network="mockapi" -v $(pwd):/app -w /app/tests/sdks/kotlin openjdk:11-jdk-slim sh -c "./gradlew test -q && cat result.txt"';
+        'docker run --network="mockapi" -v $(pwd):/app -w /app/tests/sdks/kotlin eclipse-temurin:11-jdk-jammy sh -c "./gradlew test -q && cat result.txt"';
 
     protected array $expectedOutput = [
         ...Base::PING_RESPONSE,

tests/KotlinJava17Test.php

@@ -17,7 +17,7 @@ class KotlinJava17Test extends Base
         'chmod +x tests/sdks/kotlin/gradlew',
     ];
     protected string $command =
-        'docker run --network="mockapi" -v $(pwd):/app -w /app/tests/sdks/kotlin openjdk:17-jdk-slim sh -c "./gradlew test -q && cat result.txt"';
+        'docker run --network="mockapi" -v $(pwd):/app -w /app/tests/sdks/kotlin eclipse-temurin:17-jdk-jammy sh -c "./gradlew test -q && cat result.txt"';
 
     protected array $expectedOutput = [
         ...Base::PING_RESPONSE,

tests/KotlinJava8Test.php

@@ -17,7 +17,7 @@ class KotlinJava8Test extends Base
         'chmod +x tests/sdks/kotlin/gradlew',
     ];
     protected string $command =
-        'docker run --network="mockapi" --rm -v $(pwd):/app -w /app/tests/sdks/kotlin openjdk:8-jdk-slim sh -c "./gradlew test -q && cat result.txt"';
+        'docker run --network="mockapi" --rm -v $(pwd):/app -w /app/tests/sdks/kotlin eclipse-temurin:8-jdk-jammy sh -c "./gradlew test -q && cat result.txt"';
 
     protected array $expectedOutput = [
         ...Base::PING_RESPONSE,