Backported opencollective post-install script to v5

Author: Sampo Kivistö

packages/inferno/package.json

@@ -31,7 +31,7 @@
     "logo": "https://opencollective.com/inferno/logo.txt"
   },
   "scripts": {
-    "postinstall": "opencollective postinstall"
+    "postinstall": "opencollective-postinstall"
   },
   "rollup": {
     "bundledDependencies": [
@@ -51,6 +51,6 @@
   "dependencies": {
     "inferno-shared": "5.6.1",
     "inferno-vnode-flags": "5.6.1",
-    "opencollective": "^1.0.3"
+    "opencollective-postinstall": "^2.0.3"
   }
 }