undo accidental changes and actually pin @types/json-schema

.github/workflows/test.yml

@@ -8,7 +8,7 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        node: [8, 9, 10, 12, 14, 15, 16]
+        node: [4, 6, 8, 9, 10, 11, 12, 13, 14, 15, 16]
     name: Node ${{ matrix.node }}
     steps:
       - uses: actions/checkout@v2
@@ -18,6 +18,14 @@ jobs:
         with:
           node-version: ${{ matrix.node }}
 
+      - name: Upgrade Node <= 5 npm
+        run: npm install -g npm@3
+        if: ${{ matrix.node <= 5 }}
+
+      - name: Upgrade Node 7 npm
+        run: npm install -g npm@6
+        if: ${{ matrix.node == 7 }}
+
       - run: npm install
 
       - name: Setup

package.json

@@ -39,6 +39,7 @@
     "@babel/preset-env": "7.10.4",
     "@typescript-eslint/eslint-plugin": "4.10.0",
     "@typescript-eslint/parser": "4.10.0",
+    "@types/json-schema": "7.0.3",
     "@types/node": "16.11.23",
     "acquit": "1.x",
     "acquit-ignore": "0.1.x",