Update supported Node versions

Author: AndrewJo

package.json

@@ -30,7 +30,7 @@
   },
   "homepage": "https://github.com/VerdigrisTech/nitrous#readme",
   "engines": {
-    "node": ">=8.0.0"
+    "node": ">=10.0.0"
   },
   "optionalDependencies": {
     "@types/memcached": "^2.2.6",