Align Sublink Headline Colour with Main Headline Colour

[DanielCliftonGuardian]

We need to make the sublink headline colour match the main headline of the cards colour.
Its currently checking the format if its a gallery, audio or video which is a problem if article in the sublink is not

dotcom-rendering/dotcom-rendering/src/paletteDeclarations.ts

Line 2490 in 9cd5a50

const cardHeadlineTextLight: PaletteFunction = (format) =>

dotcom-rendering/dotcom-rendering/src/lib/cardHelpers.ts

Line 4 in 9cd5a50

export const isMediaCard = (format: ArticleFormat): boolean => {