Adds versioning for the stats output

Address one of the bullet points from https://github.com/vercel/next.js/issues/15225 to remove unused dependencies on `dotenv` now that it's supported by default in Next.js.

The top-level script has always been `dev` so this makes the package scripts consistent

This adds a simple typing definition to the Webpack ncc output.

Fixes https://github.com/vercel/next.js/issues/21390.

`gtm.pageview` was called without sending an actual URL, while it is required here:

https://github.com/vercel/next.js/blob/36aeca8f041a81ae01cae3c55e5c187a038e4166/examples/with-google-tag-manager/lib/gtm.js#L3-L6

Changed the return values of the compare function from string values to numbers

This adds a config to output webpack's stats

This ensures we get the latest tag not relying on the order of the tags in the output

This should resolve the typing issues described in https://github.com/vercel/next.js/issues/21390 from the webpack inlining, by declaring `next/dist/compiled/webpack` in the main typing file as a source.

Co-authored-by: Nkodiakhq[bot] <49736102+kodiakhq[bot]@users.noreply.github.com>

According to [MDN docs](https://developer.mozilla.org/en-US/docs/Web/HTML/Element/a#attr-href) the page must scroll to the top with both "#" and "#top" anchors.

<img width="675" alt="Screen Shot 2020-08-27 at 7 20 19 PM" src="https://user-images.githubusercontent.com/13899924/91500693-582a5b80-e89a-11ea-803f-4592d458baba.png">

My addition of the Yarn 2 caveat was more nuanced than I thought. Apologies. @merceyz has been adding extensive e2e tests for Yarn 2 support. We plan to support Yarn 2 compat.

Reverts https://github.com/vercel/next.js/pull/21657.

As we saw some confusion with users trying out Yarn 2 and hitting roadblocks in their app. Yarn 2 is supported on a best-effort basis.

Adding test for experimental-serverless-trace + fix for the same

@timneutkens I think this is ready for a review.

I've made some changes to the original design that _seem_ to have paid off.  The parenting relationships for traces of normal builds are applied more uniformly, resulting in more intelligible traces:

<img width="900" alt="Screen Shot 2021-01-29 at 12 53 47 AM" src="https://user-images.githubusercontent.com/5016978/106253732-ba321880-61cc-11eb-98fd-d45af5078273.png">

Hot-reloading is surfaced now, too.  I will note, however, that we will want to dig in deeper and find out where the large portion of time at the beginning of hot-reload is spent.  Example:

<img width="894" alt="Screen Shot 2021-01-29 at 12 53 28 AM" src="https://user-images.githubusercontent.com/5016978/106253828-e057b880-61cc-11eb-967d-46eaff31ecef.png">

Where did those 180 ms go?  At the least, we can now track how long a hot-reload takes, and have a place to start with further investigation.

This insures we add entries for each locale version of a non-dynamic SSG page since they can have unique revalidate values. This requires a version bump in the `prerender-manifest` since the static routes now contain additional values which need to be handled separately. 

Fixes: https://github.com/vercel/next.js/issues/21568 

* Update CI docs change diff check

* Increse fetch depth for merge base detecting

* Update cancel branches config

I tried the preset provided at `packages/next-plugin-storybook` but it was raising error due to an [unsafe negation](https://eslint.org/docs/rules/no-unsafe-negation) in the `preset.js` file.

I added a test to show the error:
```
● next-plugin-storybook filterModuleRules › should filter module rules correctly

    TypeError: rule.test.test is not a function

      48 |       if (!rule.test instanceof RegExp) return true
      49 |       // use Next.js' built-in CSS
    > 50 |       if (rule.test.test('hello.css')) {
         |                     ^
      51 |         return false
      52 |       }
      53 |       // use next-babel-loader instead of storybook's babel-loader

      at filter (../packages/next-plugin-storybook/preset.js:50:21)
          at Array.filter (<anonymous>)
      at Object.filterModuleRules (../packages/next-plugin-storybook/preset.js:46:28)
      at Object.<anonymous> (unit/webpack-config-overrides.test.js:12:36)
```

Co-authored-by: Nrokobekavac0 <roko.beakavac2003@gmail.com>
Co-authored-by: NTim Neutkens <tim@timneutkens.nl>
Co-authored-by: NJoe Haddad <joe.haddad@zeit.co>

Kontent example also contains the implementation of the preview capabilities in the example.

Including the example as it is [Data fetching section](https://nextjs.org/docs/basic-features/data-fetching).