DE STF Grant Quarterly Milestone Reports

[ruddermann]

### Milestone Reports
- [ ] https://github.com/openjs-foundation/security-collab-space/issues/39
- [ ] Milestone 2: Q3 2023
- [ ] Milestone 3: Q4 2023
- [ ] Milestone 4: Q1 2024
- [ ] Milestone 5: Q2 2024
- [ ] Milestone 6: Q3 2024
- [ ] Milestone 7: Q4 2024