Gradient.GetHashCode returns different values when two Gradient objects compare equal

How to reproduce:

1. Open the attached "IN-154865" project
2. In the menu bar, select "Tools" > "Bug Repros" > "Gradient Equals and GetHashCode"
3. Observe the Console

Actual result: The Console shows "a.Equals(b): True", two different hash codes, and "HashSet containing a, Contains(b): False"
Expected result: The Console shows "a.Equals(b): True", two identical hash codes, and "HashSet containing a, Contains(b): True"

Reproducible with: 6000.0.0f1, 6000.7.0b5, 7000.0.0a9

Reproducible on: Windows 10 (by user), Windows 11 Enterprise (25H2)
Not reproducible on: No other environments tested

Workaround: Use a custom IEqualityComparer<Gradient> that hashes the keys and mode

Note: The hash values differ between Editor sessions, so the exact numbers in the Console vary