ci(workflows): add mkdocs build step to GitHub Actions workflow

test(tox): add docs environment to tox for building documentation

.github/workflows/python_package.yml

@@ -44,3 +44,6 @@ jobs:
 
       - name: Run build checks
         run: tox -e build
+
+      - name: Run mkdocs build
+        run: tox -e docs

tox.ini

@@ -19,6 +19,18 @@ commands_pre =
 commands =
     poetry install --with dev
     poetry run ruff check src
+
+[testenv:docs]
+allowlist_externals = poetry, ruff, mkdocs
+extras =
+    dev
+    docs
+deps =
+    poetry
+commands_pre =
+    #
+commands =
+    poetry install --with dev --with docs
     poetry run mkdocs build
 
 [testenv:build]
@@ -30,6 +42,7 @@ deps =
 commands_pre =
     #
 commands =
+    poetry install --with dev
     poetry build
     poetry run twine check dist/*