Add docs build workflow

.github/workflows/build_docs.yml

@@ -0,0 +1,27 @@
+name: Build docs
+
+on:
+  pull_request:
+    branches:
+      - main
+  workflow_dispatch:
+
+permissions:
+  contents: write
+
+jobs:
+  build:
+    runs-on: ubuntu-latest
+
+    steps:
+    - uses: actions/checkout@v4
+    - name: Set up Python
+      uses: actions/setup-python@v3
+      with:
+        python-version: '3.12'
+    - name: Install dependencies
+      run: |
+        python -m pip install --upgrade pip
+        pip install -e .[dev]
+    - name: Build docs
+      run: pdoc magic_list/ -n -d numpy -o docs/