[etiennelatendresse-optable]

Why

Without this feature a token past its refresh_from keeps going out to bidders until it hard-expires, visible only as falling match rates. We need to refresh a stale UID2 on every page

What changed

• A page that serves targeting from cache now refreshes a UID2 that is due, instead of handing bidders an aging token.
• The refresh finds tokens resolved by either path, targeting or tokenize, so it covers the tokens prebid actually bids with.
• Nothing is refreshed when there is no cache, no refresh material, or a token that is not yet due, so the common page makes no extra request.

[mosherBT]

LGTM let's get @jplaroche to give review as well