✨ T&Cs - Add subheadings to the table

[bradystroud]

cc @pierssinclairssw @UlyssesMaclaren

https://www.ssw.com.au/terms-and-conditions

Figure: ❌ Too many rows makes this table hard to read

Figure: ✅ Subheadings seperate sections

### Tasks
- [x] Allow users to add subheadings to categorise roles in the table using Tina
- [x] Add subheadings - Developers, SysAdmins, Designers, TV + Marketing
- [x] Seperate Data Engineers and Software Engineers
- [x] Checked by Brady then Piers
- [ ] Complete Done Video v2 for combined #939 and #933

[bradystroud]

reopening because there is 1 task remaining 🎥👀 @Harry-Ross