[Automation] Allow "Project selection" to be set as "Choose at runtime"

### Feature summary

Allow a single automation to be used across multiple projects

### What problem are you trying to solve?

I have a workflow of updating a nuget package across a dozen repositories, being able to have a single automation and on running it choosing the project would allow be to avoid having a dozen identical automations each with their own project.

### Proposed solution

Have an experience for project to be selected when running it.

### Workflow impact

Allows reuse of an automation in multiple projects

### Installation context

_No response_

### Additional context

_No response_