[SD-1454] normalise path for GA

[lambry]

Issue: https://digital-vic.atlassian.net/browse/SD-1454

What I did

• Normalise page_url for GA, the ticket mentioned this had been discuessed with FE so I'm not sure if this method or the alternate method of 301 redirecting all URLs was discussed.

Checklist

For all PR's

• I've added relevant changes to the project Readme if needed
• I've updated the documentation site as needed
• I have added tests to cover my changes (if not applicable, please state why in a comment)

For new UI components only

• I have added a storybook story covering all variants
• I have checked a11y tab in storybook passes
• I have added cypress component tests (if the component is interactive)
• Any events are emitted on the event bus using emitRplEvent