ci: drop the branch-added Windows boot-comparison soak target

The Windows flake soak workflow is dev's; this branch had grafted a one-shot
member boot comparison target and its PowerShell driver onto it. The graphs
that comparison produced are recorded as receipts, and soak loops are not a
deliverable of the O2 lane, so the workflow returns to dev's exact contents.
The platform-neutral profile and diff scripts remain.