Which data should be permanently stored in data base

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We need to decide which data provided by the user should be stored permanently in the database and which should be discarded right after the co2 emissions have been calculated.

From a data pricavacy perspective, we should try to store as less data as possible. On the other side it would be good to retrain enough information in case some of the formulas of the co2calculator package change over time (e.g. the completness score co2calculator #48). Or if we want to allow the user to edit some of their data entries after submitting them (e.g. if they made a mistake, should they be able to edit the entry or delete it and create a new one?)

The data which needs to be provided by the user is describe in https://github.com/pledge4future/WePledge/blob/dev/backend/docs/graphql_add_data_queries.md