build!: upgrade engines field to >=8.10.0 (#483)

Benjamin E. Coe · JustinBeckwith · commit 728678ac73ed · 2019-05-02T11:27:16.000-07:00
diff --git a/package.json b/package.json
@@ -94,7 +94,7 @@
   },
   "homepage": "https://github.com/googleapis/gax-nodejs#readme",
   "engines": {
-    "node": ">=6.0.0"
+    "node": ">=8.10.0"
   },
   "nyc": {
     "exclude": [
