Bump govuk-frontend from 5.5.0 to 5.6.0 (#872)

Bumps [govuk-frontend](https://github.com/alphagov/govuk-frontend) from 5.5.0 to 5.6.0.
- [Release notes](https://github.com/alphagov/govuk-frontend/releases)
- [Changelog](https://github.com/alphagov/govuk-frontend/blob/main/CHANGELOG.md)
- [Commits](alphagov/govuk-frontend@v5.5.0...v5.6.0)

---
updated-dependencies:
- dependency-name: govuk-frontend
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <[email protected]>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

package.json

@@ -12,7 +12,7 @@
   "dependencies": {
     "@govuk-prototype-kit/common-templates": "^2.0.1",
     "@x-govuk/govuk-prototype-filters": "^1.4.1",
-    "govuk-frontend": "5.5.0",
+    "govuk-frontend": "5.6.0",
     "govuk-prototype-kit": "^13.13.2",
     "task-list-component": "^0.0.4"
   }