Add specific end date to OData queries for dashboards

The OData queries for the sales graphs on the dashboards don't specify an end date, merely a start date of today() minus one year.

If we have imported sales data with dates in the future, this will massively skew the graphs.

We should make the queries to the data specifically only show data between the start date (a year ago) and today, as the graphs are intended to show the last 12 months of sales data.