Update KubernetesResourceUtil.java

[ArunErram]

Fix issue eclipse-jkube#2580: null-check

Description

Fixes # (issue)
eclipse-jkube#2580

Type of change

• Bug fix (non-breaking change which fixes an issue)
• Feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change
• Chore (non-breaking change which doesn't affect codebase;
  test, version modification, documentation, etc.)

Checklist

• [x ] I have read the contributing guidelines
• [ x] I signed-off my commit with a user that has signed the Eclipse Contributor Agreement
• [ x] My code follows the style guidelines of this project
• [ x] I Keep It Small and Simple: The smaller the PR is, the easier it is to review and have it merged
• [ x] I use conventional commits in my commit messages
• [x ] I have performed a self-review of my code
• I Added CHANGELOG entry
• I have updated the documentation accordingly
• No new bugs, code smells, etc. in SonarCloud report
• I have added tests that prove my fix is effective or that my feature works
• New and existing unit tests pass locally with my changes
• I tested my code in Kubernetes
• I tested my code in OpenShift