Area Charts : Fill color isn't applied when color is rgb()

[Slokilla]

Description

When using a rgb() color, the filling in the graph does not take into account the opacity.

Steps to Reproduce

1. Use this fill objet :

 {
        colors: ['rgb(236, 22, 26)'],
        opacity: [0.1],
        type: 'solid'
 }

See that the graph is full opaque.
2. Replace the color by the exact same hexadecimal color :

 {
        colors: ['#EC1A16'],
        opacity: [0.1],
        type: 'solid'
 }

See that this time, the graph is not opaque.

Expected Behavior

The graph should not be opaque.

Actual Behavior

Screenshots

With rgb :

With hex :

Reproduction Link

With rgb : https://codepen.io/slokilla/pen/bGXpBge

With hexa : https://codepen.io/slokilla/pen/LYwNbbM