chore: drop Node v8 support

.circleci/config.yml

@@ -18,11 +18,6 @@ commands:
       # run tests!
       - run: npm test
 jobs:
-  node-v8:
-    docker:
-      - image: circleci/node:8@sha256:44c6136b6b55003fa12321aa1eb790a5a6482edb461227cb56daf488178d04dc
-    steps:
-      - run-npm-test
   node-v10:
     docker:
       - image: circleci/node:10@sha256:5e4e5ca02096bbeb87af1fae7b42d20ff11223da7558db9cc1a31fc0f6b0ad12
@@ -37,6 +32,5 @@ jobs:
 workflows:
   multiple_builds:
     jobs:
-      - node-v8
       - node-v10
       - node-v12

.github/workflows/nodejs.yml

@@ -9,7 +9,7 @@ jobs:
 
     strategy:
       matrix:
-        node-version: [8.16, 10, 12]
+        node-version: [10, 12]
 
     steps:
     - uses: actions/checkout@v1

package.json

@@ -4,7 +4,7 @@
   "version": "2.0.8",
   "author": "Teppei Sato <teppeis@gmail.com>",
   "engines": {
-    "node": ">=8"
+    "node": ">=10"
   },
   "main": "src/index.js",
   "bin": {