Add ability to prevent OIDC redirect (#6544)

* Add ability to prevent OIDC redirect

* Fix Typing on optional boolean

* Fix lint

* Fix lint

* Rename var from PREVENT to DISABLE

---------

Co-authored-by: Tom Moor <tom@getoutline.com>

app/scenes/Login/index.tsx

@@ -229,7 +229,11 @@ function Login({ children }: Props) {
   }
 
   // If there is only one provider and it's OIDC, redirect immediately.
-  if (config.providers.length === 1 && config.providers[0].id === "oidc") {
+  if (
+    config.providers.length === 1 &&
+    config.providers[0].id === "oidc" &&
+    !env.OIDC_DISABLE_REDIRECT
+  ) {
     window.location.href = getRedirectUrl(config.providers[0].authUrl);
     return null;
   }