Add ability to skip shim generation

### Checklist

- [x] I have verified this is the correct repository for opening this issue.
- [x] I have verified no other issues exist related to my request.

### Is Your Feature Request Related To A Problem? Please describe.

Shim generation can be fine in one environment, but not work in another non-standard environment. To stop the generation of shims, you have a few options, but as shim generation is a package task, all of them involve changing the package.

### Describe The Solution. Why is it needed?

To allow shim generation to be controlled, we should provide a command line option to prevent shim generation for an install or upgrade.

### Additional Context

_No response_

### Related Issues

- https://github.com/chocolatey/home/issues/137

No files, tests, or entry points are named. Start by locating the package task and the install or upgrade command-option handling, then trace where shim generation is invoked; done means a command-line option can suppress shims during both installation and upgrade without changing the package.

Written by the indexing model from the issue text.