fix: update Dockerfile to use Eclipse Temurin JDK 17 instead of OpenJDK

[vikashkrdeveloper]

Description

This PR fixes the Java executor build failure caused by an unavailable Docker base image tag.

The Java executor image has been updated from openjdk:17-alpine to eclipse-temurin:17-jdk-alpine, which is a maintained and available JDK 17 Alpine image. This ensures executor image builds complete successfully during setup and CI.

Why This Change

• openjdk:17-alpine is no longer reliably available
• Build pipeline failed while creating the Java executor image
• Replacing it restores stable Docker builds without changing application behavior

Scope

• Updates only the Java executor base image
• No API changes
• No runtime logic changes
• No breaking changes expected

Validation

• Java executor Docker image builds successfully with the new base image
• Other executor images and workflows remain unaffected