Fix styling on documentation sidebar (#1395)

* fix sidebar stling in docs theme

* don't display heading levels higher than 3 in sidebar

* update sitemap step for easier debugging

* add matrix so github doesn't get confused

.github/workflows/docs.yaml

@@ -22,6 +22,11 @@ jobs:
   accessibility:
     if: contains(toJson(github.event.commits), '[ci skip]') == false
     runs-on: ubuntu-latest
+    strategy:
+      fail-fast: true
+      matrix:
+        python-version: [ 3.9 ]
+        os: [ ubuntu-latest ]
 
     steps:
     - uses: actions/checkout@v2
@@ -29,7 +34,7 @@ jobs:
     - name: Set up Python
       uses: actions/setup-python@v2
       with:
-        python-version: 3.9
+        python-version: ${{ matrix.python-version }}
 
     - name: Setup Node.js environment
       uses: actions/setup-node@main
@@ -61,8 +66,16 @@ jobs:
       env:
         site_url: http://127.0.0.1:8000
       run: |
+        filename='sitemap.xml'
         select="{urls: [\"${site_url}/\", \"${site_url}/search.html?q=jrnl\", .urlset.url[].loc]}"
-        curl -s "$site_url/sitemap.xml" | poetry run xq "$select" > list.json
+
+        curl -s "${site_url}/${filename}" > $filename
+
+        echo "::group::${filename}"
+        cat $filename
+        echo '::endgroup::'
+
+        poetry run xq "$select" $filename > list.json
 
     - name: Accessibility testing (Pa11y)
       run: pa11y-ci -c list.json