message: Update core package link
  the core package link file name is `core.md`, not `core-package.md`.
diff: @@ -11,7 +11,7 @@ prior knowledge.
  - [**React/Preact**](./react-preact.md) covers how to work with the bindings for React/Preact.
  - [**Vue**](./vue.md) covers how to work with the bindings for Vue 3.
  - [**Svelte**](./svelte.md) covers how to work with the bindings for Svelte.
  -- [**Core Package**](./core-package.md) defines why a shared package exists that contains the main
  +- [**Core Package**](./core.md) defines why a shared package exists that contains the main
  logic of `urql`, and how we can use it directly in Node.js.
  After reading the page for your bindings and the "Core" page you may want to the next two pages in
  