feat: adding support for fr language 🌎🇫🇷

[Grraahaam]

Description 📣

Adding support for fr language.

This pull request refers to this issue : #181 (Help us translate Infisical)

I had to change some frontend code as well to make the changes work as expected, I'm not an expert so please take a look ✌️

👀 - looking for help, ✔️ - ready, ⚠️ - in progress

Files	Status
activity	✔️
billing	✔️
commom	✔️
dashboard	✔️
integrations	✔️
login	✔️
nav	✔️
section-incident	✔️
section-members	✔️
section-password	✔️
section-token	✔️
settings-members	✔️
settings-org	✔️
settings-personal	✔️
settings-project	✔️
signup	✔️

inspired by #199

Concerns

I'm wondering about the below meanings :

// frontend/public/locales/en/section-members.json
"org-members-description": "...These users could afterwards be formed into projects.",

// frontend/public/locales/en/settings-org.json
"description": "...These users could afterwards be formed into projects."

How could users be "formed into projects"? IMO the wording isn't pretty clear in that case

Moreover, by testing the changes I've made with the latest version I had, some translation don't seem to be applied... AFAIK it seems to be related to the next-i18n namespace concept : https://www.i18next.com/principles/namespaces (Edit: seems to be fixed now with the latest Infisical commits)

But there's still some hard-coded text at some places, I guess it'll be fixed with time ✌️

Tests 🛠️

Follow the development setup to test it locally : https://infisical.com/docs/contributing/developing

# Build and launch the Infisical app
make up-dev

# Reach to your web browser and type
https://localhost:8080

# Change language to `fr`
# Dropdown list in the top right corner, and let the fun begin

[vmatsiiako]

Thank you so much once again @Grraahaam! This is amazing!