link to dashboard from sidebar does not work when httpNodeRoot is set

[Steve-Mcl]

Reported on forum: https://discourse.nodered.org/t/dashboard-2-0-pre-alpha-available/80142/86?u=steve-mcl

[Steve-Mcl]

I have the fix for this as I needed to get it working to review #164

Main.js

/**
 * Configure SocketIO Client to Interact with Node-RED
 */
// inspect the current URL to determine the correct path to use
const url = new URL(window.location.href)
// determine the base path to use (everything before the first /dashboard) // TODO: determine what to do when /dashboard is called something else (support multiple dashboards github #1 )
const basePath = url.pathname.split('/dashboard')[0]
const path = basePath + '/dashboard/socket.io'
const socket = io({
    path
})

ui_base.html

    function uiLink (name, path) {
        const base = RED.settings.httpNodeRoot || '/'
        const basePart = base.endsWith('/') ? base : `${base}/`
        const dashPart = path.startsWith('/') ? path.slice(1) : path
        const fullPath = `${basePart}${dashPart}`
        return `<div class="red-ui-sidebar-header"><label>${name}</label><a id="open-dashboard" href="${fullPath}" target="nr-dashboard" class="editor-button editor-button-small nr-db-sb-list-header-button">Open Dashboard<i style="margin-left: 3px;" class="fa fa-external-link"></i></a></div>`
    }