Add matrix on Node.js versions

```yml
jobs:
test:
runs-on: ubuntu-latest
strategy:
matrix:
node: [ '10', '12', '14', '16' ]
# This project supports all active/current Node.js versions at
# https://nodejs.org/en/about/releases/
name: Node ${{ matrix.node }} test
steps:
- uses: actions/checkout@v2
- uses: actions/setup-node@v2
with:
node-version: ${{ matrix.node }}
cache: npm
- run: npm ci
- run: npm run lint
- run: npm run test
env:
FORCE_COLOR: 1
ENABLE_GAS_REPORT: true
- run: npm run test:inheritance
- name: Print gas report
run: cat gas-report.txt
```