remove an extra whitespace.

spec.bs

@@ -936,7 +936,7 @@ To <dfn>validate and convert auction ad config</dfn> given an {{AuctionAdConfig}
 
     Note: The JavaScript code calling {{Navigator/runAdAuction()}} is responsible for resolving
       |config|["{{AuctionAdConfig/directFromSellerSignalsHeaderAdSlot}}"] only when the {{Promise}}
-      returned from an associated {{WindowOrWorkerGlobalScope/fetch()}} that was made  with the
+      returned from an associated {{WindowOrWorkerGlobalScope/fetch()}} that was made with the
       {{RequestInit/adAuctionHeaders}} option set to `true` resolves or rejects. Otherwise, there
       will be a race condition that the worklet can run without the direct from seller signals that
       it needs. See [handling direct from seller signals](#handling-direct-from-seller-signals) for