Transfer description only when it exist

This fixes JavaScript errors with newer GitLab repositories where description is null.

Author: ViliusS

src/index.ts

@@ -237,7 +237,12 @@ async function transferDescription() {
 
  let project = await gitlabApi.Projects.show(settings.gitlab.projectId);
 
- await githubHelper.updateRepositoryDescription(project.description);
+ if (project.description) {
+ await githubHelper.updateRepositoryDescription(project.description);
+ console.log('Done.');
+ } else {
+ console.log('Description is empty, nothing to transfer.')
+ }
 }
 
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