fix(gatsby-link): fix navigate method type

* Fixes type of navigate method

The usage of the original navigation function type created problems when using spreaded parameters. Since the navigate implementation in gatsby does not have the same call signature as @reach/router anyways (the promise returned by @reach/router is ignored), it is easier to define our own interface than to overwrite the types from @reach/router.

* Replace interface and define parameter overloading inline;

---------

Co-authored-by: Philippe Serhal <[email protected]>

Author: pajosieg

packages/gatsby-link/index.d.ts

@@ -1,5 +1,5 @@
 import * as React from "react"
-import { NavigateFn, LinkProps } from "@reach/router" // These come from `@types/reach__router`
+import { NavigateOptions, LinkProps } from "@reach/router" // These come from `@types/reach__router`
 
 // eslint-disable-next-line @typescript-eslint/naming-convention
 export interface GatsbyLinkProps<TState> extends LinkProps<TState> {
@@ -33,7 +33,10 @@ export class Link<TState> extends React.Component<
  * Sometimes you need to navigate to pages programmatically, such as during form submissions. In these
  * cases, `Link` won’t work.
  */
-export const navigate: (...args: Parameters<NavigateFn>) => void;
+export const navigate: {
+  (to: string, options?: NavigateOptions<{}>): void
+  (to: number): void
+}
 
 /**
  * It is common to host sites in a sub-directory of a site. Gatsby lets you set the path prefix for your site.