extensions/html-language-features/server/src/requests.ts/joinPath
export function joinPath(uriString: string, ...paths: string[]): string {
	const uri = URI.parse(uriString);
	const parts = uri.path.split('/');
	for (const path of paths) {
		parts.push(...path.split('/'));
	}
	return uri.with({ path: normalizePath(parts) }).toString();
}