Add page load to tracking metrics

What does this MR do and why?

This MR adds tracking metrics to when the security training urls are loading. It does not introduce any UI/UX changes.

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How to set up and validate locally

Numbered steps to set up and validate the change are strongly suggested.

MR acceptance checklist

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• I have evaluated the MR acceptance checklist for this MR.

Related to #355479 (closed)