computeDestinationPoint uses a different hardcoded earth radius value instead of the constant

in computeDestinationPoint.ts

```
const computeDestinationPoint = (
    start: GeolibInputCoordinates,
    distance: number,
    bearing: number,
    radius: number = 6371000
) => {

```

instead of using  export const earthRadius = 6378137; from constants.ts

this issue appeared in v2.0.25
