remove preview

.github/workflows/preview.yml

@@ -1,33 +0,0 @@
-name: Deploy PR previews
-concurrency: preview-${{ github.ref }}
-on:
-  pull_request:
-    types:
-      - opened
-      - reopened
-      - synchronize
-      - closed
-jobs:
-  deploy-preview:
-    runs-on: ubuntu-latest
-    steps:
-      - uses: actions/checkout@v2
-      - uses: ruby/setup-ruby@v1
-        with:
-          ruby-version: 2.7
-          bundler-cache: true
-      - name: Setup Node
-        uses: actions/setup-node@v2
-        with:
-          node-version: '14'
-      - run: npm install
-      - name: Build site
-        uses: limjh16/jekyll-action-ts@v2
-        with:
-          enable_cache: true
-      - uses: rossjrw/pr-preview-action@v1
-        with:
-          source-dir: .
-          preview-branch: gh-pages
-          umbrella-dir: _site/pr-preview
-          action: auto