update minimal required node version to 10 (Debnium)

Signed-off-by: BinotaLIU <me@binota.org>

.travis.yml

@@ -1,7 +1,6 @@
 language: node_js
 
 node_js:
-  - "lts/carbon"
   - "lts/dubnium"
   - "11"
   - "12"
@@ -12,7 +11,6 @@ cache: npm
 matrix:
   fast_finish: true
   include:
-    - node_js: lts/carbon
     - node_js: lts/dubnium
   allow_failures:
     - node_js: "11"

package.json

@@ -204,7 +204,7 @@
     "utf-8-validate": "~5.0.1"
   },
   "engines": {
-    "node": ">=8.0.0 <12.0.0"
+    "node": ">=10.0.0 <13.0.0"
   },
   "maintainers": [
     {