Run `chocolateyBeforeModify.ps1` by default on reinstallations

Started on https://github.com/chocolatey-community/chocolatey-coreteampackages/pull/1517:

> I just noticed one problem:
>
> 1. Install this package
> 2. Open Code Insiders
> 3. Force reinstall
>
> It will fail because `chocolateyBeforeModify.ps1` does not run before a reinstallation.
>
> I'll make it run in `chocolateyInstall.ps1` so. By the way, I suggest considering run `chocolateyBeforeModify.ps1` by default on reinstallations.

This would help both users trying to reinstall a package and also users who had the package installed by other means and wanted to reinstall using Chocolatey.

Start by reviewing the reinstall reproduction steps and the linked chocolatey-coreteampackages pull request. Inspect chocolateyBeforeModify.ps1 and chocolateyInstall.ps1, then trace the reinstall flow to determine when the pre-modification script runs. Done means reinstalling a package runs chocolateyBeforeModify.ps1 by default without breaking the force-reinstall scenario.

Written by the indexing model from the issue text.