fix: cancel a review (#7454)

- Fixes #7152
- If a review no longer has any pending comments, remove that review from the database.

Reviewed-on: https://codeberg.org/forgejo/forgejo/pulls/7454
Reviewed-by: Gusted <gusted@noreply.codeberg.org>
Co-authored-by: Leni Kadali <lenikadali@noreply.codeberg.org>
Co-committed-by: Leni Kadali <lenikadali@noreply.codeberg.org>

services/issue/comments_test.go

@@ -69,6 +69,7 @@ func TestDeleteComment(t *testing.T) {
 		}))
 		hookTaskCount := unittest.GetCount(t, &webhook_model.HookTask{})
 
+		require.NoError(t, comment.LoadReview(t.Context()))
 		require.NoError(t, issue_service.DeleteComment(db.DefaultContext, nil, comment))
 
 		// The comment doesn't exist anymore.
@@ -77,6 +78,8 @@ func TestDeleteComment(t *testing.T) {
 		assert.Equal(t, issue.NumComments, unittest.AssertExistsAndLoadBean(t, &issues_model.Issue{ID: comment.IssueID}).NumComments)
 		// No notification was fired for the deletion of this comment.
 		assert.Equal(t, hookTaskCount, unittest.GetCount(t, &webhook_model.HookTask{}))
+		// The review doesn't exist anymore.
+		unittest.AssertNotExistsBean(t, &issues_model.Review{ID: comment.ReviewID})
 	})
 }