[18.0][ADD] l10n_fr_einvoicing: neutralize script

[remi-filament]

Fixes #54

[ak-git-bot]

Hi @alexis-via,
some modules you are maintaining are being modified, check this out!

[risto42]

Thanks for implementing this! Two issues in neutralize.sql, both verified on a real database:

1. fr_ctc_secret_id does not exist — the column is fr_ctc_client_secret, so the script fails outright.
2. SET … = False on varchar columns: PostgreSQL casts the boolean to the string 'false', which is truthy on the ORM side — fr_ctc_accredited_platform would still look configured after neutralization. Use = NULL instead.

[remi-filament]

Hi @risto42 thanks for double checking, it was too late yesterday I mixed things up !
Both points should be fixed.
Best Regards !