Removed unneeded workflows.

deleted:    .github/workflows/0-welcome.yml
deleted:    .github/workflows/1-enable-github-pages.yml
deleted:    .github/workflows/2-configure-your-site.yml
deleted:    .github/workflows/3-customize-your-homepage.yml
deleted:    .github/workflows/4-create-a-blog-post.yml
deleted:    .github/workflows/5-merge-your-pull-request.yml

Author: it176131