Tab completion / autocomplete does not work on a Raspberry Pi

- Platform/operating system (i.e. Raspberry Pi with Raspbian operating system,
Windows 32-bit, Windows 64-bit, Mac OSX 64-bit, etc.): Raspberry Pi 4 Model B Rev 1.1 - Raspbian GNU/Linux 11 (bullseye)

- CircUp, A CircuitPython module updater. Version 2.0.4

- Python version (run `python -version` or `python3 -version`): Python 3.9.2

- Error message you are receiving, including any Python exception traces: Tab completion / autocomplete does not work on a Raspberry Pi

- List the steps to reproduce the problem below (if possible attach code or commands
to run):
For example:

Using the example from the docs, it does NOT Work

circup install n + tab -circup install neopixel (+tab: offers neopixel and neopixel_spi completions)

circup install a + tab -circup install adafruit\_ + m a g + tab -circup install adafruit_magtag

No source file, test, or CLI entry point is named in the issue. First reproduce the documented `circup install` tab-completion commands on the Raspberry Pi/Raspbian and compare their behavior with the expected completions; done means autocomplete works for both examples.

Written by the indexing model from the issue text.