Sponsorship Admin Page - Send Notifications/Emails: add viewable full history of notifications sent

[oliviasauls]

Location of change python.org/admin/sponsors/sponsoremailnotificationtemplate/ - Admin/Sponsorships/Sponsor Email Notification Templates

Describe the solution you'd like

• View full history of notifications sent (to all sponsors)

Reason for change

• So admin can see which sponsors have received each notification/easier to track sponsorship communications

Priority 2. Medium

Date Needed Sponsorship Launch

Additional context