Update ONS logo alt text

[precious-onyenaucheya-ons]

What is the context of this PR?

Fixes https://github.com/ONSdigital/ons-service-manual-website/issues/385

Updated the alt text for the ons logo image link to provide a more accurate description of its content or purpose. Additionally, assigned the role of 'image' to the SVG

How to review this PR

Check that

• the ons logo image has a role of image
• the alt text of the image link is updated to 'office for national statistics homepage'

Checklist

This needs to be completed by the person raising the PR.

• I have selected the correct Assignee
• I have linked the correct Issue

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[rmccar]

Reading the DAC issue I don't think this addresses the ask. The word logo hasn't been removed from the alt text but has been removed from the class name which seems to have broken the logo link focus state. I think the alt text should be something a bit more succinct like "Office for National Statistics homepage". We will also need the Welsh translation for this too.

[alessioventuriniAND]

As richard's said maybe Hafan needs to be capitalised. Apart from that it looks good now. Rather than having just "Office for National Statistics homepage" in the title of the svg maybe we can say this : "Link to Office for National Statistics homepage" ?

[rmccar]

As richard's said maybe Hafan needs to be capitalised. Apart from that it looks good now. Rather than having just "Office for National Statistics homepage" in the title of the svg maybe we can say this : "Link to Office for National Statistics homepage" ?

I think it should just be "Office for National Statistics homepage" according to the research I have done. https://www.w3.org/TR/WCAG20-TECHS/H30.html example 2 on this page is an example of our use case here

I think the Welsh translation I provided on this PR still does need to be properly checked though