refactor: initialize config via APP_INITIALIZER

Closes #181

src/app/modules/about/about-page/about-page.component.ts

@@ -23,7 +23,7 @@ import {ConfigProvider} from '../../config/config.provider';
   styleUrls: ['about-page.scss'],
 })
 export class AboutPageComponent implements OnInit {
-  content: Promise<SCAboutPage>;
+  content: SCAboutPage;
 
   constructor(
     private readonly route: ActivatedRoute,
@@ -33,12 +33,11 @@ export class AboutPageComponent implements OnInit {
   async ngOnInit() {
     const route = this.route.snapshot.url.map(it => it.path).join('/');
 
-    this.content = new Promise(resolve => {
-      this.configProvider
-        .getValue('aboutPages')
-        .then(value =>
-          resolve((value as SCAppConfiguration['aboutPages'])[route] ?? {}),
-        );
-    });
+    this.content =
+      (
+        this.configProvider.getValue(
+          'aboutPages',
+        ) as SCAppConfiguration['aboutPages']
+      )[route] ?? {};
   }
 }