Assign-to-Share: update "Recent Activity" CSV export

[TylerHendrickson]

Subtask of [STORY]: Change "assign" feature to "share" #2823

Blocked by

• 3060

Blocks

N/A

Definition of Done

CSVs generated in Finder from Dashboard -> Recent Activity -> See All Activity -> Export to CSV are updated so that the current Grant Assigned By column/key is renamed to Grant Shared By.

Implementation Details

• This CSV is generated by the /organizations/<organizationId>/grants/exportCSVRecentActivities API route. The main required change for this issue is cosmetic, and simply needs to update the arguments to the csvStringify() call in that route handler.
• This change does need to be gated by a feature flag, and only effective when the SHARE_TERMINOLOGY_ENABLED environment variable evaluates to "true".

[ClaireValdivia]

This is looking great in staging, thanks @mayabose !