We should discuss dropping the support of Azure v1 reports.

Based on the analysis the azure_line_items Trino table in prod, it seems that the only schema that uses v1 reports is our demo schema - as this was the only schema with populated "usagedatetime" and "currency" columns.

In addition, Azure now allows you to select the version of the dataset to export. An analysis of the column names in the oldest available version of the export (2019-10-01) showed that even this old version follows the column name logic of v2 reports.

Although no customers seem to be using v1 reports, if we decide to drop the support, we should still announce this to customers and mention it in docs.

Also, we could update Nise to generate RG vs. subscription based exports instead of v1 vs. v2 reports rather then just removing v1 reports.