Restoring Red Hat Satellite 6.16 or 6.17 fails complaining about db duplicates on CREATE UNIQUE INDEX

Issue

• Restoring Satellite 6.16 (or 6.17) fails with:

  pg_restore: while PROCESSING TOC:
  pg_restore: from TOC entry 4967; 1259 20295 INDEX index_fact_names_on_name_and_type foreman
  pg_restore: error: could not execute query: ERROR: could not create unique index "index_fact_names_on_name_and_type"
  DETAIL: Key (name, type)=(lscpu_flags, Katello::RhsmFactName) is duplicated.
  Command was: CREATE UNIQUE INDEX index_fact_names_on_name_and_type ON public.fact_names USING btree (name, type);
  
  pg_restore: from TOC entry 5507; 1259 3233544 INDEX index_katello_installed_packages_on_nvrea foreman
  pg_restore: error: could not execute query: ERROR: could not create unique index "index_katello_installed_packages_on_nvrea"
  DETAIL: Key (nvrea)=(gcc-objc++-4.8.5-44.el7.x86_64) is duplicated.
  Command was: CREATE UNIQUE INDEX index_katello_installed_packages_on_nvrea ON public.katello_installed_packages USING btree (nvrea);
  
  pg_restore: from TOC entry 5637; 1259 4054876 INDEX katello_available_module_streams_name_stream_context foreman
  pg_restore: error: could not execute query: ERROR: could not create unique index "katello_available_module_streams_name_stream_context"
  DETAIL: Key (name, stream, context)=(pmdk, 1_fileformat_v6, d63f516d) is duplicated.
  Command was: CREATE UNIQUE INDEX katello_available_module_streams_name_stream_context ON public.katello_available_module_streams USING btree (name, stream, context);