Move OAuth2 redirect intructions to generic snippet

components/snippets/oauth2redirect.mdx

@@ -0,0 +1,8 @@
+The OAuth2 Redirect URI is the location where the provider will redirect to after trying to login. This needs to set to your Postiz `FRONTEND_URL` + `/integrations/social/` + `providername`.
+
+* eg: If your Postiz URL is: `https://postiz.example.com`, then your OAuth2 Redirect URI is `https://postiz.example.com/integrations/social/`.
+* eg: If your Postiz URL is `https://localhost:5000`, then your OAuth2 Redirect URI is `https://localhost:5000/integrations/social/providername`.
+
+You only need to set one OAuth2 Redirect URI when you are setting up your Postiz app.
+
+{{ provider }}

pages/providers/discord.mdx

@@ -4,6 +4,7 @@ description: How to add discord to your system
 ---
 
 import {Steps, Callout} from "nextra/components";
+import OAuth2Redirect from "../../components/snippets/oauth2redirect.mdx";
 
 <Callout>
 This integration requires that you have **Manage Server** permissions on the Discord server you want to integrate with.
@@ -29,6 +30,8 @@ DISCORD_CLIENT_SECRET="your_client_secret"
 
 ### Add a Redirect URI
 
+<OAuth2Redirect />
+
 The redirect URI is the URL that Discord will redirect to after you have logged in. Assuming you are running Postiz on `postiz.example.com`, this would be: `https://postiz.example.com/integrations/social/discord`. Alternatively if you are running on `localhost:4200`, this would be `http://localhost:4200/integrations/social/discord`. You only really need one of these, depending on where you are running Postiz.
 
 You can find this in the **OAuth2** section of the Discord Developer Portal.