chore(deps): drop Node 8, add 12 and 15

chriskrycho · chriskrycho · commit 8930499f57d6 · 2020-11-13T12:15:30.000-07:00
BREAKING CHANGE: Node 8 is long since out of LTS support
diff --git a/package.json b/package.json
@@ -64,7 +64,7 @@
     "testdouble": "3.16.0"
   },
   "engines": {
-    "node": "8.* || >= 10.*"
+    "node": "10.* || 12.* || >= 14.*"
   },
   "ember-addon": {
     "configPath": "tests/dummy/config",
