Use json schema validator directly for p_ci_job_definitions.config.

What does this MR do and why?

As titled, use json schema validator directly instead of the intermit method validate_config_json_schema for p_ci_job_definitions.config.

After the change, we will enforce the json schema validation instead of silently logging the schema errors.

References

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Before	After

How to set up and validate locally

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Related to #581845 (closed)