fix: fix comment at release pr is ugly (#2348)

Co-authored-by: Jeff Ching <chingor@google.com>

Author: goatwu1993

src/manifest.ts

@@ -1240,7 +1240,7 @@ export class Manifest {
  const releaseList = githubReleases
  .map(({tagName, url}) => `- [${tagName}](${url})`)
  .join('\n');
- const comment = `:robot: Created releases:\n${releaseList}\n:sunflower:`;
+ const comment = `🤖 Created releases:\n\n${releaseList}\n\n:sunflower:`;
  await this.github.commentOnIssue(comment, pullRequest.number);
  }