Update dependencies (#32)

* Update dependencies
* Drop Node 12 from build matrix
* Adds Node 17 and 18 to build matrix

Author: Brian Kelly

.github/workflows/build.yml

@@ -7,7 +7,7 @@ jobs:
     runs-on: ubuntu-latest
     strategy:
       matrix:
-        node-version: [12.x, 14.x, 15.x, 16.x]
+        node-version: [14.x, 15.x, 16.x, 17.x, 18.x]
     steps:
       - uses: actions/checkout@v2
       - name: Use Node.js ${{ matrix.node-version }}