Fix: Enable deals for soft aliases

[Pubmatic-Supriya-Patil]

This PR solves issue mentioned in #3362

[bsardo]

@Pubmatic-Supriya-Patil see my comment on the corresponding PR. I think we can still attempt to normalize the bidder name and if normalization fails, we can continue processing so that soft aliases are handled properly instead of skipping the bidder:

bidderNormalized, bidderFound := openrtb_ext.NormalizeBidderName(bidder.String())
if !bidderFound {
	... // handle soft aliases here
}