Revert "Remove workflow to build and deploy docs"

This reverts commit 812db6a.

Author: duckontheweb

.github/workflows/deploy_mkdocs.yml

@@ -0,0 +1,55 @@
+name: Publish docs via GitHub Pages
+
+on:
+  push:
+    branches:
+      - master
+    paths:
+      # Rebuild website when docs have changed or code has changed
+      - 'README.md'
+      - 'docs/**'
+      - 'mkdocs.yml'
+      - '**.py'
+
+jobs:
+  build:
+    name: Deploy docs
+    runs-on: ubuntu-latest
+
+    steps:
+      - name: Checkout master
+        uses: actions/checkout@v3
+
+      - name: Set up Python 3.8
+        uses: actions/setup-python@v3
+        with:
+          python-version: 3.8
+
+      - name: Install dependencies
+        run: |
+          python -m pip install --upgrade pip
+          python -m pip install -e \
+            stac_fastapi/api \
+            stac_fastapi/types \
+            stac_fastapi/extensions \
+            stac_fastapi/sqlalchemy
+          python -m pip install mkdocs mkdocs-material pdocs
+
+      - name: update API docs
+        run: |
+          pdocs as_markdown \
+            --output_dir docs/api/ \
+            --exclude_source \
+            --overwrite \
+            stac_fastapi
+        env:
+          POSTGRES_USER: username
+          POSTGRES_PASS: password
+          POSTGRES_DBNAME: postgis
+          POSTGRES_HOST: localhost
+          POSTGRES_PORT: 5432
+          POSTGRES_HOST_READER: localhost
+          POSTGRES_HOST_WRITER: localhost
+
+      - name: Deploy docs
+        run: mkdocs gh-deploy --force