Curve tangents cannot be weighted in Visual Effects curves

Steps to reproduce:

1. Create and open a new project
2. Install the "Visual Effects Graph" in 'Window -> Package Management -> Package Manager'
3. Create and open a new VFX "Simple Burst" graph in 'Assets -> Create -> Visual Effects -> Visual Effect Graph'
4. Open the curve editor in the "Size Over Life" node
5. Right-click on any one key in the Curve window
6. Select 'Both Tangents -> Weighted' in the context menu
7. Observe the Curve window

Actual results: The tangent is still not weighted

Expected results: The tangent becomes weighted

Reproducible with versions: 6000.0.0f1, 6000.0.79f1, 6000.3.20f1, 6000.5.4f1, 6000.6.0b4, 6000.7.0a3

Tested on (OS): Windows 11 Pro (25H2)