...
2.4. In the field 'Fields' type a list of fields separated by line break sign (\n). This is the list of API Name fields that will be transmitted into a description of the incident in PagerDuty. If you add “-” in this field, it For example,
CA10__subject__c\n
CA10__closeDate__c\n
CA10__status__c\n
CA10__description__c\n
If you use “-” before a field API Name, this field won't be added into a description of the incident (e.g. - Id - will exclude 'Record ID').
...