README Update Suggestion

Hello, I've been working with BitstreamEvolution for a bit and wanted to note a possible inconsistency with the README, as it may help future people who use the repo.

Specifically, the README states that BitstreamEvolution requires Python version 3.7 or higher. Personally, I encountered an error when running evolve.py when using Python 3.8:

This was thrown for the Circuit.py file, line 33

in Circuit def get_bitstream(self) -> list[int]: TypeError: 'type' object is not subscriptable

After looking up the issue, it seemed like this is a type hinting feature only supported by Python version 3.9 and higher. This was confirmed when the issue went away for me after switching to Python 3.9. Would making this change to the README be helpful?

Comprueba el requisito de versión de Python en README y compáralo con la anotación de tipo indicada en Circuit.py en la línea 33 cuando evolve.py se ejecuta con Python 3.8. Se considera terminado cuando README indica correctamente la versión mínima de Python compatible y refleja el requisito observado.

Escrito por el modelo de indexación a partir del texto del issue.