UMD component exports have duplicate names

[colinrotherham]

Description of the issue

GOV.UK Frontend v5 beta releases include Universal Module Definition (UMD) bundles for:

1. Entire package as all.bundle.js
2. Individual components as accordion.bundle.js, button.bundle.js etc

This appears to be related to workarounds added (see #2426, #2829, #2899) to rename default (unnamed) exports when older Rollup releases didn't support named exports in the same bundle

See the following componentPathToModuleName() helper for context:

govuk-frontend/packages/govuk-frontend/rollup.publish.config.mjs

Lines 49 to 51 in 4d13a75

	// Components are given names (e.g window.GOVUKFrontend.Accordion)
	amd: { id: componentPathToModuleName(input) },
	name: componentPathToModuleName(input)

Since we moved to named exports in b94e812 as part of #3771 we can likely remove the helper to fix the issue

Steps to reproduce the issue

When using individual component bundles, code using existing require() calls (CommonJS, AMD) or window global properties no longer work and must be updated to use duplicate names instead:

- const { Accordion } = window.GOVUKFrontend
+ const { Accordion } = window.GOVUKFrontend.Accordion