npm v7 (#107)

* Upgrade lockfile version

* Remove redundant `install-self-peers` dependency

* Bump `class-validator-jsonschema`

* Upgrade to Node 16 in CI

Author: epiphone

.github/workflows/test.yml

@@ -11,6 +11,8 @@ jobs:
     steps:
       - uses: actions/checkout@v2
       - uses: actions/setup-node@v1
+        with:
+          node-version: 16
       - run: npm ci
       - run: npm run build
       - run: npm run test:format