Update crown image

[matteason]

Just a heads up, in case you weren't already aware, that the GOV.UK crown is being updated soon to match the new royal cypher: alphagov/govuk-frontend#4058

Petitions uses the crown in several places, eg on government responses: https://petition.parliament.uk/petitions/636546?reveal_response=yes#response-threshold

Affected images are:

https://github.com/alphagov/e-petitions/blob/master/app/assets/images/graphics/graphic_crown.png
https://github.com/alphagov/e-petitions/blob/master/app/assets/images/graphics/graphic_crown-white.png
https://github.com/alphagov/e-petitions/blob/master/app/assets/images/graphics/graphic_crown-2x.png
https://github.com/alphagov/e-petitions/blob/master/app/assets/images/graphics/graphic_crown-white-2x.png

[pixeltrix]

@matteason thanks for the heads up - will let the Parliament team know about it.

[pixeltrix]

@matteason I assume we'll need to update the coat of arms in the footer as well at some point but we're waiting on the College of Arms to prepare the new rendering?

[matteason]

@pixeltrix Afraid I'm not sure what's happening with the coat of arms - it's been asked about here: alphagov/govuk-frontend#4019 (comment)

I assume that's going to be a more drawn-out process since the coat of arms is more complicated visually and it's featured in (most) departmental logos too, which will all need updating

[matteason]

The new crown is rolling out across GOV.UK over the next two weeks - it's on the main site now: https://www.gov.uk/government/news/govuk-launches-new-official-crown-logo-for-his-majesty-the-king