[Bugfix] the Manifest Syntax error (#1524)

Fixes the Manifest Syntax error

src/main/resources/static/css/error.css

@@ -1,8 +1,3 @@
-p {
-  text-align: center;
-  margin-top: 2em;
-}
-
 .features-container {
   display: grid;
   grid-template-columns: repeat(auto-fill, minmax(21rem, 3fr));

src/main/resources/static/manifest.json

@@ -3,12 +3,12 @@
   "short_name": "Stirling-PDF",
   "icons": [
     {
-      "src": "/android-icon-192x192.png",
+      "src": "/android-chrome-192x192.png",
       "sizes": "192x192",
       "type": "image/png"
     },
     {
-      "src": "/android-icon-512x512.png",
+      "src": "/android-chrome-512x512.png",
       "sizes": "512x512",
       "type": "image/png"
     }

src/main/resources/static/site.webmanifest

@@ -1,17 +1,17 @@
 {
-    "name": "Stirling PDF",
-    "short_name": "Stirling PDF",
+    "name": "Stirling-PDF",
+    "short_name": "Stirling-PDF",
     "icons": [
-        {
-            "src": "/android-chrome-192x192.png",
-            "sizes": "192x192",
-            "type": "image/png"
-        },
-        {
-            "src": "/android-chrome-512x512.png",
-            "sizes": "512x512",
-            "type": "image/png"
-        }
+      {
+        "src": "/android-chrome-192x192.png",
+        "sizes": "192x192",
+        "type": "image/png"
+      },
+      {
+        "src": "/android-chrome-512x512.png",
+        "sizes": "512x512",
+        "type": "image/png"
+      }
     ],
     "theme_color": "#ffffff",
     "background_color": "#ffffff",