Mouse actions on prompt generates error on one-cli execution

Found a bug? Please fill out the sections below. 👍

### Issue Summary

A summary of the issue.

## Steps to Reproduce the Problem

1. type `one workspace change`
2. when the prompt comes up with a list, hit any part of the prompt with mouse cursor.
error:
Traceback (most recent call last):
File "/usr/local/bin/one", line 8, in
sys.exit(main())
File "/usr/local/lib/python3.8/site-packages/one/__main__.py", line 5, in main
cli()
File "/usr/local/lib/python3.8/site-packages/click/core.py", line 829, in __call__
return self.main(*args, **kwargs)
File "/usr/local/lib/python3.8/site-packages/click/core.py", line 782, in main
rv = self.invoke(ctx)
File "/usr/local/lib/python3.8/site-packages/click/core.py", line 1259, in invoke
return _process_result(sub_ctx.command.invoke(sub_ctx))
File "/usr/local/lib/python3.8/site-packages/click/core.py", line 1259, in invoke
return _process_result(sub_ctx.command.invoke(sub_ctx))
File "/usr/local/lib/python3.8/site-packages/click/core.py", line 1066, in invoke
return ctx.invoke(self.callback, **ctx.params)
File "/usr/local/lib/python3.8/site-packages/click/core.py", line 610, in invoke
return callback(*args, **kwargs)
File "/usr/local/lib/python3.8/site-packages/one/commands/workspace.py", line 38, in change
f.write('WORKSPACE=' + answers['workspace'] + '\n')
KeyError: 'workspace'

Any other relevant information. For example, why do you consider this a bug and what did you expect to happen instead?

## Specifications

- Version: Run `one --version`: one, version 0.5.1
- Platform: (macOS / Linux): macOs
- Installation method: (Binary / PyPI): PyPI