Allow forcing HTTPS in URL generation (#92)

* Force HTTPS feature
* Add docs

custom_components/auth_oidc/helpers.py

@@ -4,12 +4,14 @@ from homeassistant.components import http
 from .views.loader import AsyncTemplateRenderer
 
 
-def get_url(path: str) -> str:
+def get_url(path: str, force_https: bool) -> str:
     """Returns the requested path appended to the current request base URL."""
     if (req := http.current_request.get()) is None:
         raise RuntimeError("No current request in context")
 
     base_uri = str(req.url).split("/auth", 2)[0]
+    if force_https:
+        base_uri = base_uri.replace("http://", "https://")
     return f"{base_uri}{path}"