Import collection file chooser won't allow to select multiple files

### Expected Behavior

When we click on import button, file chooser will open, but it won't allow to choose multiple files

### Actual Behavior

It should allow choosing multiple files, so that we can import multiple file at one go

### Reproduction Steps

1. Go to import collection
2. Choose file

### Is there an existing issue for this?

- [X] I have searched the [issue tracker](https://www.github.com/Kong/insomnia/issues) for this problem.

### Additional Information

_No response_

### Insomnia Version

2023.5.8

### What operating system are you using?

macOS

### Operating System Version

Mac OS

### Installation method

download

### Last Known Working Insomnia version

2023.5.8

Start at the import collection flow and reproduce the file chooser behavior on macOS using multiple files. Trace how the chooser is configured and verify that selecting multiple files imports them in one operation. Done means the chooser accepts multiple files without regressing single-file imports.

Written by the indexing model from the issue text.