Fix regression with 'None' inserted in html by google analytics script (#404)

Author: jorisvandenbossche

pydata_sphinx_theme/__init__.py

@@ -288,6 +288,8 @@ def generate_google_analytics_script(id):
                 """
             soup = bs(script, "html.parser")
             return soup
+        else:
+            return ""
 
     context["generate_nav_html"] = generate_nav_html
     context["generate_toc_html"] = generate_toc_html