Fix flaky static initialization error

[reakaleek]

As seen in https://github.com/elastic/docs-builder/actions/runs/15775018706/job/44467383605?pr=1403#step:5:96

[github-actions]

Label error. Requires exactly 1 of: automation, breaking, bug, changelog:skip, chore, ci, dependencies, documentation, enhancement, feature, fix, redesign. Found:

[Mpdreamz]

This is sadly not a long term fix, since the initialization might happen on any test following this pattern which is all.

Its static so that it will be shared amongs every instance of the type. Each [Fact] method will instantiate a new instance of the containing type.

Removing static alone would thus be enough to ensure each gets a non shared instance.

The static/lazy stuff might be a premature optimalization on my end.