fix typo

Author: msukkari

docs/self-hosting/upgrade/v3-to-v4-guide.mdx

@@ -55,7 +55,7 @@ Unfortunately, multi-tenancy mode is no longer officially supported in v4. To up
 to finish upgrading to v4 in single-tenant mode.
 
 ## Troubleshooting
-- If you're hitting issues with sigining into your Sourcebot instance, make sure you're setting `AUTH_URL` correctly to your deployment domain (ex. `https://sourcebot.yourcompany.com`)
+- If you're hitting issues with signing into your Sourcebot instance, make sure you're setting `AUTH_URL` correctly to your deployment domain (ex. `https://sourcebot.yourcompany.com`)
 
 
 Having troubles migrating from v3 to v4? Reach out to us on [discord](https://discord.gg/6Fhp27x7Pb) or [GitHub discussion](https://github.com/sourcebot-dev/sourcebot/discussions/categories/support) and we'll try our best to help