fix(PPDSC-2480): load correct font urls

[mstuartf]

PPDSC-2480

What

1. Background - why this is needed
   Font file not loading for Virgin so incorrect font displaying in Storybook theme checker
2. What did you do

• Old Montserrat font link was invalid
• Instead of hardcoding the new one, add a link element to load a stylesheet that imports the fonts
• This matches what Virgin do on their site

3. What does the reviewers should expect
   Virgin fonts display correctly in theme checker

I have done:

• Written unit tests against changes
• Written functional tests against the component and/or NewsKit site
• Updated relevant documentation

I have tested manually:

• The feature's functionality is working as expected on Chrome, Firefox, Safari and Edge
• The screen reader reads and flows through the elements as expected.
• There are no new errors in the browser console coming from this PR.
• When visual test is not added, it renders correctly on different browsers and mobile viewports (Safari, Firefox, small mobile viewport, tablet)
• The Playground feature is working as expected

Before:

After:

Who should review this PR:

How to test:

[newskit-engineering]

You can preview these changes on:
Documentation Site: http://ncu-newskit-docs.s3-website-eu-west-1.amazonaws.com/ppdsc-2480-virgin-fonts
Storybook: http://ncu-newskit-docs.s3-website-eu-west-1.amazonaws.com/ppdsc-2480-virgin-fonts/storybook

[mutebg]

to me personally, that's the simplest solution!

[Xin00163]

Pretty neat. How did you find this? @mstuartf

[mstuartf]

I looked at the Virgin site and that's how they load their fonts there. I think the reason that this stopped working is that the old google fonts url was out of date / invalid. But this way we shouldn't have this problem again.