Bump next and storybook-addon-next-router

Bumps [next](https://github.com/vercel/next.js) and [storybook-addon-next-router](https://github.com/lifeiscontent/storybook-addon-next-router). These dependencies needed to be updated together.

Updates `next` from 12.3.4 to 15.0.3
- [Release notes](https://github.com/vercel/next.js/releases)
- [Changelog](https://github.com/vercel/next.js/blob/canary/release.js)
- [Commits](vercel/next.js@v12.3.4...v15.0.3)

Updates `storybook-addon-next-router` from 3.1.1 to 4.0.2
- [Release notes](https://github.com/lifeiscontent/storybook-addon-next-router/releases)
- [Commits](lifeiscontent/storybook-addon-next-router@v3.1.1...v4.0.2)

---
updated-dependencies:
- dependency-name: next
  dependency-type: direct:production
- dependency-name: storybook-addon-next-router
  dependency-type: direct:development
...

Signed-off-by: dependabot[bot] <[email protected]>