Update outdated automated issues

[sjspielman]

These automated issues will no longer be needed in their current form. Their templates should be either removed from setup-issue-templates and the associated lines can be removed from the GHA that files the issues, OR the templates should be reframed to match the current setup.

• Issues we can probably remove (but check that it still makes sense when we get there!)
  • setup-issue-templates/update-header-pages.md
  • setup-issue-templates/tailor-to-workshop-content.md (these tasks should be able to be handled automatically by #106 config variables)
• Remove setup-issue-templates/delete-directories-and-rename.md
• Update scope setup-issue-templates/update-config.md
  • Also will need to account for variables added in #106
• Update to handle new approach to notebooks which will not involve htmlpreview: setup-issue-templates/draft-schedule.md & setup-issue-templates/final-schedule.md

[sjspielman]

When updating update-config.md, consider this as well: https://github.com/AlexsLemonade/training-specific-template/issues/76#issuecomment-1717569941 (issue #76 is therefore being closed in favor of this issue).

[sjspielman]

Closed by #136