fix: Set home workspace as first available for user

The default Build Workspace may not be available for all users
depending on Role/Permissions settings. To handle this, instead of
assuming everyone gets Build, we'll dynamically pick from the
available workspaces instead

(cherry picked from commit 3b42738947)

frappe/public/js/frappe/desk.js

@@ -289,7 +289,7 @@ frappe.Application = class Application {
 		}
 		if (!frappe.workspaces['home']) {
 			// default workspace is settings for Frappe
-			frappe.workspaces['home'] = frappe.workspaces['build'];
+			frappe.workspaces['home'] = frappe.workspaces[Object.keys(frappe.workspaces)[0]];
 		}
 	}