RubiconBidAdapter singleRequest bidder config is not working

[elad-yosifon]

Type of issue

A bug

Description

RubiconBidAdapter singleRequest config is not working anymore due to caching the "initial" config in a module scope, instead of dynamically using it.

Steps to reproduce

adding this configuration with pbjs.que.push will not be memoized by the rubiconBidAdapter current code:

pbjs.que.push(() => {
  pbjs.setConfig({
    rubicon: {
      singleRequest: true
    }
  });
});

Expected results

setting singleRequest: true should trigger only one request per auction

Actual results

setting singleRequest: true is ignored

Platform details

• since Prebid.js version 4.10.0

Other information

This is a regression, it used to work before this commit 92e234c.
#5780

[dgirardi]

Closing since #9050 was merged.