feat(only-labels): add 2 new options to distinguish issue and PR configs (#336)

* feat(assignees): add new option to avoid stale for assignees

closes #271

* test: add more coverage

* docs: fix readme format issue

* docs: reorder and enhance typo

* docs(contributing): add more information about the npm scripts

* feat(only-labels): add new options to customize it for issues and PR

closes #308

src/classes/issue.spec.ts

@@ -28,6 +28,8 @@ describe('Issue', (): void => {
       exemptIssueLabels: '',
       exemptPrLabels: '',
       onlyLabels: '',
+      onlyIssueLabels: '',
+      onlyPrLabels: '',
       operationsPerRun: 0,
       removeStaleWhenUpdated: false,
       repoToken: '',