Fix site.webmanifest to enable Actual to be installed as Chromium PWA (#2202)

packages/desktop-client/public/site.webmanifest

 {
-    "name": "",
-    "short_name": "",
+    "name": "Actual",
+    "short_name": "Actual",
     "icons": [
         {
             "src": "/android-chrome-192x192.png",
@@ -15,5 +15,6 @@
     ],
     "theme_color": "#ffffff",
     "background_color": "#ffffff",
-    "display": "standalone"
+    "display": "standalone",
+    "start_url": "."
 }

upcoming-release-notes/2202.md

+---
+category: Enhancements
+authors: [subnut]
+---
+
+Fix site.webmanifest to make Actual installable as a Chromium PWA