[ci] migrate docs build to github actions

.github/workflows/build_docs.sh

@@ -0,0 +1 @@
+sphinx-versioning --use-master-conf --use-master-templates build --greatest-tag --whitelist-branches master docs/source docs/build/html

.github/workflows/docs.yml

@@ -0,0 +1,36 @@
+name: Build docs
+
+on:
+  push:
+    branches: [master]
+    tags: ["v*"]
+  release:
+    types: [published]
+
+jobs:
+  build-deploy:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v2
+      - uses: actions/setup-python@v2
+        with:
+          python-version: 3.7
+
+      - uses: actions/cache@v2
+        with:
+          path: ~/.cache/pip
+          key: pip-${{ hashFiles('requirements-dev.txt') }}-${{ hashFiles('docs/requirements.txt') }}
+
+      - name: Install docs deps
+        run: bash .github/workflows/install_docs_deps.sh
+
+      - name: Build docs
+        run: bash .github/workflows/build_docs.sh
+
+      - name: deploy docs
+        uses: peaceiris/actions-gh-pages@v3
+        with:
+          github_token: ${{ secrets.GITHUB_TOKEN }}
+          publish_dir: docs/build/html
+          publish_branch: gh-pages
+          commit_message: Deploy pytorch/ignite docs

.github/workflows/install_docs_deps.sh

@@ -0,0 +1,6 @@
+# remove pkg-resources as it causes failure when installing https://github.com/vfdev-5/sphinxcontrib-versioning
+pip uninstall -y pkg-resources setuptools && pip install --upgrade setuptools
+pip install torch torchvision -f https://download.pytorch.org/whl/cpu/torch_stable.html -U
+pip install -r requirements-dev.txt
+pip install -r docs/requirements.txt
+pip install git+https://github.com/vfdev-5/sphinxcontrib-versioning.git

docs/source/conf.py

@@ -103,7 +103,7 @@
     "logo_only": True,
 }
 
-html_logo = "_static/img/ignite_logo.svg"
+html_logo = "_templates/_static/img/ignite_logo.svg"
 
 html_favicon = "_templates/_static/img/ignite_logomark.svg"
 
@@ -188,7 +188,7 @@
 # -- Options for intersphinx extension ---------------------------------------
 
 # Example configuration for intersphinx: refer to the Python standard library.
-intersphinx_mapping = {"https://docs.python.org/": None}
+intersphinx_mapping = {"https://docs.python.org/3/": None}
 
 # -- Options for todo extension ----------------------------------------------