Add missing package.json respository.url fields

[colinrotherham]

This PR hopefully solves the last requirement for:

• Add trusted publishing for npm package #329

We didn't have a package.json repository.url field

npm error code E422
npm error 422 Unprocessable Entity - PUT https://registry.npmjs.org/nhsuk-react-components - Error verifying sigstore provenance bundle: Failed to validate repository information: package.json: "repository.url" is "", expected to match "https://github.com/NHSDigital/nhsuk-react-components" from provenance

[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud