add tapadIdSystem to downloads (prebid#2658)

Author: moeroach94

download.md

@@ -568,6 +568,9 @@ Prebid.js is open source software that is offered for free as a convenience. Whi
 <label><input type="checkbox" moduleCode="sharedIdSystem" class="bidder-check-box"> Shared ID</label>
 </div></div>
 <div class="col-md-4"><div class="checkbox">
+<label><input type="checkbox" moduleCode="tapadIdSystem" class="bidder-check-box"> Tapad ID</label>
+</div></div>
+<div class="col-md-4"><div class="checkbox">
 <label><input type="checkbox" moduleCode="unifiedIdSystem" class="bidder-check-box"> Unified ID</label>
 </div></div>
 <div class="col-md-4"><div class="checkbox">