DLTP-213 Reworking on function to write fedora message to custom channel

Adding function to write message to  custom channel

Adding rspec-given
Log exception that occured on attaching files
Spec to test the new config method

Combining DLTP-189  Replace blue warning edit button to orange warning resolve button empty file

Renaming this message to `fedora_integrity_message_delivery` makes more sense. I "call" a service.