Fix issue where ui.baseUrl cannot be overridden in environment variables because it's not listed in default-app-config.ts

Author: tdonohue

src/config/default-app-config.ts

@@ -44,6 +44,9 @@ export class DefaultAppConfig implements AppConfig {
     port: 4000,
     // NOTE: Space is capitalized because 'namespace' is a reserved string in TypeScript
     nameSpace: '/',
+    // Specify the public URL that this user interface responds to. This corresponds to the "dspace.ui.url" property in your backend's local.cfg.
+    // The baseUrl is used for redirects and SEO links (in robots.txt).
+    baseUrl: 'http://localhost:4000',
 
     // The rateLimiter settings limit each IP to a 'max' of 500 requests per 'windowMs' (1 minute).
     rateLimiter: {