don't delete from params in CommunicationChannelsController

refs CNVS-16685

Change-Id: Ifbffb4b8d30871733faae3289bcb09d3d6218ca8
Reviewed-on: https://gerrit.instructure.com/44289
Tested-by: Jenkins <jenkins@instructure.com>
Reviewed-by: Rob Orton <rob@instructure.com>
QA-Review: Cody Cutrer <cody@instructure.com>
Product-Review: Cody Cutrer <cody@instructure.com>