Fixes pygraphviz failure when building wheels

One needs to install graphviz over the system package manager before
installing pygraphviz to prevent an automatic build that fails. This can
is achieved widh `sudo apt-get install graphviz graphviz-dev`.

We also add the `workflow_dispatch` event so we can run the workflow
manually.

.github/workflows/publish-docs.yml

@@ -2,14 +2,20 @@ name: publish-docs
 on:
   push:
     branches:
-    - main
+    #- main
+workflow_dispatch:
 
 permissions:
   contents: write
 
 jobs:
   deploy:
     runs-on: ubuntu-latest
+    timeout-minutes: 30
+    strategy:
+      matrix:
+        python-version: ['3.12']
+
     steps:
 
     - uses: actions/checkout@v4
@@ -18,21 +24,19 @@ jobs:
       run: |
         git config user.name github-actions[bot]
         git config user.email github-actions[bot]@users.noreply.github.com
-
-    - uses: actions/setup-python@v5
+    - name: Set up Python ${{ matrix.python-version }}
+      uses: actions/setup-python@v5
       with:
-        python-version: 3.12
+        python-version: ${{ matrix.python-version }}
 
-    - run: echo "cache_id=$(date --utc '+%V')" >> $GITHUB_ENV
+    - name: Install hatch
+      run: |
+        pip install --upgrade pip
+        pip install hatch
 
-    - uses: actions/cache@v4
-      with:
-        key: mkdocs-material-${{ env.cache_id }}
-        path: .cache
-        restore-keys: |
-          mkdocs-material-
+    - name: Install Graphviz
+      run: sudo apt-get install graphviz graphviz-dev
 
     - name: "Build and deploy docs to gh-pages"
       run: |
-        pip install hatch
         hatch run docs:deploy --force