feat: Add the ability to cleanup all (or at least many) bazel workspaces

[JesseTatasciore]

When user is attempting to clean up all bazel workspaces from their disk we will:

1. Process the workspaces to find out how large they are and when they were last used.
2. Prompt the user to find out if they would like to remove them
3. Delete those workspaces selected for deletion by the user

Both the processing and deletion of the workspaces are done in separate threads in an attempt to provide a smoother user experience

[CLAassistant]

All committers have signed the CLA.

[alexeagle]

seems like it just gets stuck in a loop if I say No

% ./bazel-bin/cmd/aspect/aspect_/aspect clean
✔ Reclaim disk space for all Bazel workspaces
? Workspace: Unknown Workspace, Age: 37h54m10.254816344s, Size: 356.52 KB. Would you like to remove?? [y/N]
? Workspace: Unknown Workspace, Age: 37h54m10.254816344s, Size: 356.52 KB. Would you like to remove?? [y/N]
? Workspace: Unknown Workspace, Age: 37h54m10.254816344s, Size: 356.52 KB. Would you like to remove?? [y/N]
? Workspace: Unknown Workspace, Age: 37h54m10.254816344s, Size: 356.52 KB. Would you like to remove?? [y/N]
? Workspace: Unknown Workspace, Age: 37h54m10.254816344s, Size: 356.52 KB. Would you like to remove?? [y/N]
? Workspace: Unknown Workspace, Age: 37h54m10.254816344s, Size: 356.52 KB. Would you like to remove?? [y/N]
? Workspace: Unknown Workspace, Age: 37h54m10.254816344s, Size: 356.52 KB. Would you like to remove?? [y/N]

[JesseTatasciore]

Related tickets for completing some of the missing work:
#210
#211