Fix install example in "Visualize" tab in docs

[mor10]

Where does the documentation need improvement?
https://mlco2.github.io/codecarbon/visualize.html

What needs to be changed?
The installation code snippet currently reads:

pip install codecarbon[carbonboard]

This causes a "no matches found: codecarbon[carbonboard]" error in zsh and other places.

To avoid unexpected errors, the example should read:

pip install 'codecarbon[carbonboard]'

Additional context
The issue is explained here pypa/pip#11842

Shells like zsh have glob qualifiers that will error if an extra is not quoted. While the glob qualifiers can be disabled, adding quotes guards against errors if people are copy-pasting or do not know that they can disable the behavior.