fix: install correct size for icons in .deb package

Credits to @AulonSal that suggested reviewing
https://github.com/sindresorhus/caprine/pull/1420

Fix #115

app/package.json

@@ -45,7 +45,7 @@
           ]
         }
       ],
-      "icon": "icon.png",
+      "icon": "icons/",
       "category": "Development",
       "synopsis": "Database manager for SQL Server, MySQL, PostgreSQL, MongoDB and SQLite",
       "publish": [
@@ -103,4 +103,4 @@
   "optionalDependencies": {
     "msnodesqlv8": "^2.0.10"
   }
-}
+}