fix: `--context` value is not auto completed using `config get`

[jooola]

TL;DR

hcloud config get token --allow-sensitive --context <tab><tab> does not autocomplete with the context name, but with filenames.

Expected behavior

The auto-completion should propose context names.

Observed behavior

The auto-completion is proposing filenames.

Minimal working example

hcloud config get token --allow-sensitive --context <tab>

Log output

No response

Additional information