- introduce new mode configuration (replaces commitMode) with the option for PR, COMMIT or HYBRID (whereas hybrid has commits and PRs alongside)

- introduce new default commit configuration automatically used if `COMMIT` mode is configured. this uses a label extractor to support conventional commits

__tests__/transform.test.ts

@@ -457,7 +457,7 @@ it('Commit SHA-1 in commitMode', async () => {
     fetchReviewers: false,
     fetchReleaseInformation: false,
     fetchReviews: false,
-    commitMode: true,
+    mode: 'COMMIT',
     configuration: customConfig,
     repositoryUtils: repositoryUtils
   })
@@ -479,7 +479,7 @@ it('Release Diff', async () => {
     fetchReviewers: false,
     fetchReleaseInformation: true,
     fetchReviews: false,
-    commitMode: true,
+    mode: 'COMMIT',
     configuration: customConfig,
     repositoryUtils: repositoryUtils
   })