Prebid 6.10.0 breaks the floor module (regression - Urgent)

[JulieLorin]

Type of issue

This is a bug, very much linked to issue #8023

Description

The floor prices module is broken for the schema fields adUnitCode (and I think for gptSlot but I didn't test)

Steps to reproduce

I used the following floorSettings :

fields: [ 'adUnitCode' ],
      values: [
        { adUnitCode: 'dfp_ban_atf', floor: 1 },
      ],
      default: 0.5

When I have a bid of 0.4$ for dfp_ban_atf, it is filtered by the floor module (expected)
When I have a bid of 0.6$ for dfp_ban_atf, it is not filtered by the floor module (but it should)

Other information

The bug comes from this PR :
https://github.com/prebid/Prebid.js/pull/7885/files#diff-52e7e567c667b4e2850bccc09785b9d48c3edb905487955df6437d7fc32eb216

This is because the bidRequest field is not populated anymore for the bidResponses.
This has been modified this way :

But the issue is that the property adUnitCode doesn't exist on bidResponses, only on bidRequests.

So when bidRequest is null, (bidRequest || bidResponse).adUnitCode this gives bidResponse.adUnitCode, which is undefined. So the floor matching cannot work for adUnitCode on bid responses