chore: remove remains of jekyll (#2068)

## Description

Remove remains of jekyll as no longer used by this repo.

## Pipeline Reference

N/A

## Type of Change

<!-- Use the check-boxes [x] on the options that are relevant. -->

- [x] Update to CI Environment or utlities (Non-module effecting
changes)
- [ ] Azure Verified Module updates:
- [ ] Bugfix containing backwards compatible bug fixes, and I have NOT
bumped the MAJOR or MINOR version in `version.json`:
- [ ] Someone has opened a bug report issue, and I have included "Closes
#{bug_report_issue_number}" in the PR description.
- [ ] The bug was found by the module author, and no one has opened an
issue to report it yet.
- [ ] Feature update backwards compatible feature updates, and I have
bumped the MINOR version in `version.json`.
- [ ] Breaking changes and I have bumped the MAJOR version in
`version.json`.
  - [ ] Update to documentation

## Checklist

- [x] I'm sure there are no other open Pull Requests for the same
update/change
- [ ] I have run `Set-AVMModule` locally to generate the supporting
module files.
- [ ] My corresponding pipelines / checks run clean and green without
any errors or warnings

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.prettierignore

@@ -1,4 +1,3 @@
 avm/
 modules/
 package-lock.json
-docs/jekyll