fix: Fix readme of full scheduled scan plugin

[trend-jack-c-tang]

fix: Fix readme of full scheduled scan plugin

Change Summary

Fix the template file name and add a link to the raw file.

PR Checklist

• [x] I've read and followed the Contributing Guide.
• Documents/Readmes
  • [x] Updated accordingly
  • [ ] Not required
• Plugins that have versioning
  • [ ] Version bumped and follows Semantic Versioning
  • [x] Not required

Other Notes