Merge conflicts were resolved in:

    item-page-title-field.component.html
      upstream heading level accessibility fix plus local customization
      to allow italics in item titles

    metadata-field-wrapper.component.html
      upstream heading level accessibility fix plus local customization
      to use "Persistent Identifier" as the URI label

To fix build issues with the merged code, additional changes were made to:

    angular.json - remove comment from standard JSON format file
    i18n/en.json - add missing comment after label definition

The error with the missing comment appears to have occured due to a difference
in opinion and/or expectations with whether the last item in a comma separated
list should/does have a trailing comma.