chore: Remove env variables in webpack bundle (#1353)

* chore: Remove env variables in webpack bundle

* remove unused globals

* refactor: consolidate window.env calls to single file

* fix: Slack client side integration auth

* fix: developers url

server/api/auth.js

@@ -51,7 +51,7 @@ function filterServices(team) {
 
 router.post("auth.config", async ctx => {
   // If self hosted AND there is only one team then that team becomes the
-  // brand for the knowledgebase and it's guest signin option is used for the
+  // brand for the knowledge base and it's guest signin option is used for the
   // root login page.
   if (process.env.DEPLOYMENT !== "hosted") {
     const teams = await Team.findAll();