Reindent manifest.json (#13544)

Now it's properly indented to 2-space.

templates/pwa/manifest_json.tmpl

@@ -1,31 +1,31 @@
 {
-    "short_name": "Gitea",
-    "name": "Gitea - Git with a cup of tea",
-    "icons": [
-      {
-        "src": "{{StaticUrlPrefix}}/img/gitea-lg.png",
-        "type": "image/png",
-        "sizes": "880x880"
-      },
-      {
-        "src": "{{StaticUrlPrefix}}/img/gitea-sm.png",
-        "type": "image/png",
-        "sizes": "120x120"
-      },
-      {
-        "src": "{{StaticUrlPrefix}}/img/gitea-512.png",
-        "type": "image/png",
-        "sizes": "512x512"
-      },
-      {
-        "src": "{{StaticUrlPrefix}}/img/gitea-192.png",
-        "type": "image/png",
-        "sizes": "192x192"
-      }
-    ],
-    "start_url": "{{AppSubUrl}}/",
-    "scope": "{{AppSubUrl}}/",
-    "background_color": "#FAFAFA",
-    "display": "standalone",
-    "theme_color": "{{ThemeColorMetaTag}}"
-  }
+  "short_name": "Gitea",
+  "name": "Gitea - Git with a cup of tea",
+  "icons": [
+    {
+      "src": "{{StaticUrlPrefix}}/img/gitea-lg.png",
+      "type": "image/png",
+      "sizes": "880x880"
+    },
+    {
+      "src": "{{StaticUrlPrefix}}/img/gitea-sm.png",
+      "type": "image/png",
+      "sizes": "120x120"
+    },
+    {
+      "src": "{{StaticUrlPrefix}}/img/gitea-512.png",
+      "type": "image/png",
+      "sizes": "512x512"
+    },
+    {
+      "src": "{{StaticUrlPrefix}}/img/gitea-192.png",
+      "type": "image/png",
+      "sizes": "192x192"
+    }
+  ],
+  "start_url": "{{AppSubUrl}}/",
+  "scope": "{{AppSubUrl}}/",
+  "background_color": "#FAFAFA",
+  "display": "standalone",
+  "theme_color": "{{ThemeColorMetaTag}}"
+}