Fix broken links in auth docs

Author: JulienLavocat

docs/docs/00200-core-concepts/00500-authentication.md

@@ -14,10 +14,10 @@ to learn more about how OIDC works and why it's a great choice for authenticatio
 ## SpacetimeAuth
 
 To make it easier to get started with authentication, SpacetimeDB offers
-[SpacetimeAuth](https://spacetimedb.com/docs/spacetimeauth), a fully managed
-OIDC provider built specifically for SpacetimeDB applications. SpacetimeAuth handles
-user management, authentication flows, and token issuance, so you don't have to
-worry about building and maintaining your own authentication service.
+[SpacetimeAuth](https://spacetimedb.com/docs/core-concepts/authentication), a fully
+managed OIDC provider built specifically for SpacetimeDB applications. SpacetimeAuth
+handles user management, authentication flows, and token issuance, so you don't have
+to worry about building and maintaining your own authentication service.
 
 SpacetimeAuth is meant to be simple to use and easy to integrate with SpacetimeDB.
 While being production-ready and able to support most common use cases, it is not

docs/versioned_docs/version-1.12.0/00200-core-concepts/00500-authentication.md

@@ -14,10 +14,10 @@ to learn more about how OIDC works and why it's a great choice for authenticatio
 ## SpacetimeAuth
 
 To make it easier to get started with authentication, SpacetimeDB offers
-[SpacetimeAuth](https://spacetimedb.com/docs/spacetimeauth), a fully managed
-OIDC provider built specifically for SpacetimeDB applications. SpacetimeAuth handles
-user management, authentication flows, and token issuance, so you don't have to
-worry about building and maintaining your own authentication service.
+[SpacetimeAuth](https://spacetimedb.com/docs/core-concepts/authentication), a fully
+managed OIDC provider built specifically for SpacetimeDB applications. SpacetimeAuth
+handles user management, authentication flows, and token issuance, so you don't have
+to worry about building and maintaining your own authentication service.
 
 SpacetimeAuth is meant to be simple to use and easy to integrate with SpacetimeDB.
 While being production-ready and able to support most common use cases, it is not