Unable to pass `--refresh` when switching to a flake

[xhalo32]

Describe the bug

When running system-manager switch --flake remote_url the remote url is not refreshed. I tried passing --refresh and hoped it would be set for the nix build command, but it wasn't supported.

How to refresh the flake cache when switching to a remote url?

To Reproduce

Steps to reproduce the behavior:

1. system-manager switch to a remote git repository
2. Push changes to the repository
3. system-manager switch again, but new changes are not fetched

Expected behavior

I expect system-manager to support a command line option to refresh the cache.

System information

Ref 8182f9e3374c98a4d7a1ea212ad06b0c453cc290
On x86_64-linux

Additional context

I have a simple fix to the issue in my repository