ci(buildrelease): install python-docs-theme (#13)

fix: sphinx.errors.ThemeError: no theme named 'python_docs_theme' found (missing theme.toml?)

Author: cesarcoatl

.github/workflows/buildrelease.yml

@@ -85,7 +85,9 @@ jobs:
 
       - name: Install dependencies
         run: |
-          python -m pip install Sphinx
+          python -m pip install \
+            Sphinx \
+            python-docs-theme
         shell: bash
 
       - name: Set SPHINXBUILD environment variable