Upgrade nhsukfrontend (now with signed commits)

[alexcolbeck1]

Description

• Upgrading nhsuk-frontend to 10.1.0
• Fixing NHS components broken by the upgrade
• Moving sass files from /_sass/ to /assets/css/

Context

Getting nhsuk-frontend updated allows us to use the latest UI components such as the new header.

Type of changes

• Refactoring (non-breaking change)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would change existing functionality)
• Bug fix (non-breaking change which fixes an issue)

Checklist

• I am familiar with the contributing guidelines
• I have followed the code style of the project
• I have added tests to cover my changes
• I have updated the documentation accordingly
• This PR is a result of pair or mob programming

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Sensitive Information Declaration

To ensure the utmost confidentiality and protect your and others privacy, we kindly ask you to NOT including PII (Personal Identifiable Information) / PID (Personal Identifiable Data) or any other sensitive data in this PR (Pull Request) and the codebase changes. We will remove any PR that do contain any sensitive information. We really appreciate your cooperation in this matter.

• I confirm that neither PII/PID nor sensitive data are included in this PR and the codebase changes.

[emmagifford]

Had a quick scan of various pages to double check that the components still work correctly.

Action links, inset text and details components all look good.

Can see that the spacing and button component on the landing page have updated too.

Nice one Alex!