feat: Update FR (french) translation file for 3.1 release (#1089)
feat: Update FR (french) translation file for 3.1 release (#1089)

Updating french translation file with new strings.

Ping: 
- @dboudreau
- @dzc34
- @PhilippeVay
- @audrasjb

For french proofreading.

## Reviewer checks

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- [x] Follows the commit message policy, appropriate for next version
- [x] Has documentation updated, a DU ticket, or requires no documentation change
- [x] Includes new tests, or was unnecessary
- [x] Code is reviewed for security by: << Name here >>

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