Fix links that are broken until other pages ship.

Author: mandiwise

src/pages/learn/security.mdx

@@ -77,7 +77,7 @@ query {
 }
 ```
 
-Even when [the N+1 problem](/learn/performance/#the-n1-problem) has been remediated through batched requests to underlying data sources, overly nested fields may still place excessive load on server resources and impact API performance. 
+Even when the N+1 problem has been remediated through batched requests to underlying data sources, overly nested fields may still place excessive load on server resources and impact API performance. 
 
 For this reason, it's a good idea to limit the maximum depth of fields that a single operation can have. Many GraphQL implementations expose configuration options that allow you to specify a maximum depth for a GraphQL document and return an error to the client if a request exceeds this limit before execution begins.
 

src/pages/learn/serving-over-http.mdx

@@ -6,7 +6,7 @@ import { Callout } from "nextra/components"
 
 The GraphQL specification doesn't require paricular client-server protocols when sending API requests and responses, but HTTP is the most common choice because of its ubiquity. On this page, we'll review some key guidelines to follow when setting up a GraphQL server to operate over HTTP.
 
-Note that the guidelines that follow only apply to stateless query and mutation operations. Visit the [Subscriptions page](/learn/subscriptions) for more information on transport protocols that commonly support these requests.
+Note that the guidelines that follow only apply to stateless query and mutation operations.
 
 <Callout type="info">
 The recommendations on this page align with the detailed [GraphQL-over-HTTP specification](https://graphql.github.io/graphql-over-http/draft/) currently in development. Though not yet finalized, this draft specification acts as a single source of truth for GraphQL client and library maintainers, detailing how to expose and consume a GraphQL API using an HTTP transport. Unlike the language specification, adherence is not mandatory, but most implementations are moving towards these standards to maximize interoperability.