Replace env variable with SITE config object

src/layouts/AboutLayout.astro

@@ -1,4 +1,5 @@
 ---
+import { SITE } from "src/config";
 import Breadcrumbs from "@components/Breadcrumbs.astro";
 import Footer from "@components/Footer.astro";
 import Header from "@components/Header.astro";
@@ -14,7 +15,7 @@ export interface Props {
 const { frontmatter } = Astro.props;
 ---
 
-<Layout title={`${frontmatter.title} | ${import.meta.env.PUBLIC_SITE_TITLE}`}>
+<Layout title={`${frontmatter.title} | ${SITE.title}`}>
   <Header activeNav="about" />
   <Breadcrumbs />
   <main id="main-content">