[instrument_manager] Should permit selecting instrument subgroup

[driusan]

The instrument_manager hardcodes a value of "1" for the test subgroup (implicitly in the generate_tables_and_testNames script) since it doesn't know how the project organizes their subgroups but it does know "1" should exist and the project can update it if required. With #9324 it no longer depends on the script. It would be a good idea to have a dropdown where the user can choose what subgroup the instrument belongs to dynamically on upload.