Repository: next.js
Issue: "Paths" in __NEXT_DATA__ are picked up by Google Search Console as internal links
Labels: bug

### Verify canary release

- [X] I verified that the issue exists in the latest Next.js canary release

### Provide environment information

    Operating System:
      Platform: linux
      Arch: x64
      Version: #1 SMP Wed Feb 19 06:37:35 UTC 2020
    Binaries:
      Node: 12.17.0
      npm: 6.14.4
      Yarn: 1.22.10
      pnpm: N/A
    Relevant packages:
      next: 12.2.0
      eslint-config-next: N/A
      react: 17.0.2
      react-dom: 17.0.2

### What browser are you using? (if relevant)

N/A

### How are you deploying your application? (if relevant)

N/A

### Describe the Bug

I recognize that this might not even be something NextJS can "fix" but I just want to highlight a problem we're seeing with our NextJS sites. I know there are people from Google who actively support NextJS, and they don't expose their own services to issues / feature requests, so I thought I might as well try here. 

tl;dr anything that even remotely resembles a path, returned as part of `__NEXT_DATA__`, will be picked up by Google Search Console and used as part of its crawling scope. 

The simplest `__NEXT_DATA__` is something that looks like

```
{ ... "page":"/docs/[[...slug]]" ...}
```

As seen here: https://nextjs.org/docs/basic-features/data-fetching/get-static-props. 

During its crawls, Google matches _within_ `__NEXT_DATA__`, seemingly anything that starts with a slash, and interprets them as internal links. In the Search Console, this manifests as a non-resolvable page, e.g. `https://nextjs.org/docs/[[...slug]`, with a referrer of `https://nextjs.org/docs/basic-features/data-fetching/get-static-props` (and any other page under `/docs`). 

**Note** that in the case of this NextJS page, it might not manifest as I've described as `/docs` is a valid page. For my particular use case, using a custom server, we're seeing the issue come up as `https://blog.com/post` with referrers of blog posts (e.g. `https://blog.com/the-post-slug`) -- `/post` is our _NextJS_ page (`pages/post.js`), but is otherwise not a valid URL. Let me know if you want some concrete examples, I've tried to make this as generic as possible. 

![image](https://user-images.githubusercontent.com/1269421/187771186-ab16389b-a753-4a63-9fc4-864f6ae2c32a.png)

![image](https://user-images.githubusercontent.com/1269421/187771267-856191e3-27f2-4fcc-9846-c8bfc219bd42.png)


**Why is this an issue?**

Internal 404s are interpreted as a site quality signal. Too many of them and Google figures your site is not being maintained and lowers your overall search ranking.

I _really_ don't want to have to implement dummy pages for `/post` and other slash-prefixed strings we have in `__NEXT_DATA__`


### Expected Behavior

Path like strings in `__NEXT_DATA__` should not be considered valid internal links by Google.  

### Link to reproduction

https://nextjs.org/docs/basic-features/data-fetching/get-static-props

### To Reproduce

1. build and deploy NextJS site
2. have site crawled by Google
3. note that Google finds and crawls internal NextJS pages, and anything else returned from data-fetching fns that looks like a path
4. these pages are marked as non-crawlable in Google Search Console