Sharing resources: fixed a typo (resources)

M. Bonaventure,

I think that in French, we spell it 'ressources' but in English, it's 'resources'.
In the exercises, it's correctly spelled (resources) but not in the theory.

Regards,

Matthieu Baerts

PS: do you prefer that I report these tiny typos in the 'Issue' section?
It's just some details... but I guess it's maybe a bit better without these typos.