Fetcher INSEE: link to documentation on provider website points to French instead of English

For INSEE, the link to documentation on provider website points to French language instead of English.

For https://db.nomics.world/INSEE/ODD-LUTTE-CHANGEMENT-CLIMATIQUE, one gets

Documentation on provider website
    https://www.insee.fr/fr/statistiques/series/112938957 

when it should be

Documentation on provider website
    https://www.insee.fr/en/statistiques/series/112938957 

The second element of the URL, currently fr should be replaced by en

Tasks

• update convert.py of insee-fetcher