refactor: remove quasar typing import from tsconfig preset

[IlCallo]

What kind of change does this PR introduce? (check at least one)

• Bugfix
• Feature
• Documentation
• Code style update
• Refactor
• Build-related changes
• Other, please describe:

Does this PR introduce a breaking change? (check one)

• Yes
• No

If yes, please describe the impact and migration path for existing applications:

Users will need to create this file into their own project to compensate these changes.
We could automatically generate it as we do with flags, but the same problems of feature flags will apply (you need to run quasar dev/build to generate it).

We could also keep this on hold until Qv3, but since every TS upgrade has breaking change upgrades anyway (but only at compile time), I think we can apply this now anyway or while upgrading TS to the next minor version and ask people to perform the needed steps manually

We could also leave /// <reference types="@quasar/app" /> into quasar typings as a fallback for existing projects, which almost certaintly already import something from quasar into their code, meaning the preset change won't affect them
We can then remove the reference when releasing Qv3

EDIT: updated the PR to remove the breaking change and postpone it to Qv3 release, left a comment into the code explaining the situation

The PR fulfills these requirements:

• It's submitted to the dev branch (or v[X] branch)
• When resolving a specific issue, it's referenced in the PR's title (e.g. fix: #xxx[,#xxx], where "xxx" is the issue number)
• It's been tested on a Cordova (iOS, Android) app
• It's been tested on a Electron app
• Any necessary documentation has been added or updated in the docs (for faster update click on "Suggest an edit on GitHub" at bottom of page) or explained in the PR's description.

If adding a new feature, the PR's description includes:

• A convincing reason for adding this feature (to avoid wasting your time, it's best to open a suggestion issue first and wait for approval before working on it)

Other information:
See quasarframework/quasar-starter-kit#162 as why this has been proposed
The main reason is to make TS automatically include @types/* packages again, which right now must be done by hand as we use types option

That PR should be merged and pushed into master before this one
This PR will then require a release of both quasar and @quasar/app packages

This PR spawned from some comments into #10277