Add device list command

[polldo]

Motivation

This PR introduces the device commands to delete and retrieve devices
Thus, now devices can be created, deleted and listed

Change description

To list devices, no flags or arguments are needed, the command is simply
$ iot-cloud-cli device list

To delete a device, a device id should be specified
$ iot-cloud-cli device delete -i <DEVICE_ID>

maybe worth doing in the future:

• list command could accept a list of IDs that should be retrieved from the cloud
  edit: a new show command might be better
  - delete could take the device id as an argument instead of using a --id flag
  edit: according to https://clig.dev/#arguments-and-flags flags are suggested over arguments

Additional Notes

Reviewer checklist

• PR address a single concern.
• PR title and description are properly filled.
• Changes will be merged in main.
• Changes are covered by tests.
• Logging is meaningful in case of troubleshooting.
• History is clean, commit messages are meaningful (see CONTRIBUTING.md) and are well formatted.

[zmoog]

LGTM!

[polldo]

split and merged in #22 and #21