Remove deprecated Chocolatey helper functions

The following Chocolatey helper functions have been deprecated and should be removed in v1.0.0:

* `Write-FileUpdateLog` (see [docs](https://docs.chocolatey.org/en-us/create/functions/write-fileupdatelog))
* `Write-ChocolateySuccess` (see [docs](https://docs.chocolatey.org/en-us/create/functions/write-chocolateysuccess))
* `Write-ChocolateyFailure` (see [docs](https://docs.chocolatey.org/en-us/create/functions/write-chocolateyfailure))
* `Install-ChocolateyDesktopLink` (see [docs](https://docs.chocolatey.org/en-us/create/functions/install-chocolateydesktoplink))

Related to Chocolatey CLI https://github.com/chocolatey/choco/issues/2469