Bidders imds, synacormedia define endpoints for the same syncer key

[josecu]

When I run Prebid Server with the configuration below, I get the following error.

jcabalugaz@arcspan prebid-server-go % ./prebid-server
F0125 18:50:01.920778   11653 main.go:53] prebid-server failed: user sync (1 error):
  1: bidders imds, synacormedia define endpoints (iframe and/or redirect) for the same syncer key, but only one bidder is permitted to define endpoints

// pbs.yaml
gdpr:
  default_value: false

I believe this issue was introduced when #2508 was merged. It seems that the usersync iframe/redirect keys should be defined in imds.yaml or synacormedia.yaml but not both.