🐛 Update deprecated package opn (#525)

> The package has been renamed to `open`
- https://www.npmjs.com/package/opn

Author: perguth

lib/cmd-inspect.js

@@ -1,5 +1,5 @@
 var disc = require('disc')
-var open = require('opn')
+var open = require('open')
 var path = require('path')
 var pump = require('pump')
 var os = require('os')

package.json

@@ -57,7 +57,7 @@
     "nanoraf": "^3.0.1",
     "nanotiming": "^7.2.0",
     "on-idle": "^3.1.4",
-    "opn": "^5.3.0",
+    "open": "^6.3.0",
     "p-wait-all": "^1.0.0",
     "pino": "^4.10.4",
     "pino-colada": "^1.4.2",