progress-stepper: Fails contrast for the grey line on white background

[saiponnada]

I verified there's no existing issue for this bug.

• There are no existing issues

Current behavior

https://webaim.org/resources/contrastchecker/?fcolor=C7C7C7&bcolor=FFFFFF

Expected behavior

The contrast of the incomplete tracking steps against the white background has a contrast of at least 3.0:1

[saiponnada]

Pending appropriate color token from Design team.

[randybascue]

color-foreground-secondary is the value to use

[saiponnada]

Pending final approval from design on what color to use(--color-neutral-500 vs --color-neutral-600). And weather to apply only on ring vs hr before the ring

[saiponnada]

Discussed with @randybascue, We decided to only update the progress stepper ring color(use --color-stroke-default aka --color-neutral-500) for now.