kibana: fail on error and improve log messages

[AndersonQ]

What does this PR do?

When parsing KINABA_URL it fail on error and improve the logging.

Why is it important?

It improves our ability to quickly diagnose an issue when the tests fail

Checklist

• My code follows the style guidelines of this project
  - [ ] I have commented my code, particularly in hard-to-understand areas
  - [ ] I have made corresponding changes to the documentation
  - [ ] I have made corresponding change to the default configuration files
  - [ ] I have added tests that prove my fix is effective or that my feature works
  - [ ] I have run the Unit tests (make unit-test), and they are passing locally
  - [ ] I have run the End-2-End tests for the suite I'm working on, and they are passing locally
  - [ ] I have noticed new Go dependencies (run make notice in the proper directory)

Related issues

• Relates Revive the Fleet and Upgrade E2E tests elastic-agent#1174

[mergify]

This pull request does not have a backport label. Could you fix it @AndersonQ? 🙏
To fixup this pull request, you need to add the backport labels for the needed
branches, such as:

• backport-v./d./d./d is the label to automatically backport to the 7./d branch. /d is the digit
  NOTE: backport-skip has been added to this pull request.

[elasticmachine]

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Build stats

• Start Time: 2022-11-04T13:22:02.495+0000

• Duration: 68 min 53 sec

Test stats 🧪

Test	Results
Failed	0
Passed	216
Skipped	0
Total	216

💚 Flaky test report

Tests succeeded.

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