Add GitHub action to lint JSON

.github/workflows/main.yml

+# copied from Liam's workflows
+
+name: CI
+
+on:
+  push:
+    branches:
+      - "master"
+  pull_request:
+    branches:
+      - "master"
+
+jobs:
+  lint-json:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v2
+      - name: Install modules
+        run: npm install
+      - name: Lint
+        run: yarn run lint
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package.json

+{
+  "name": "obsidian-community-releases",
+  "scripts": {
+    "lint": "eslint . --ext .json"
+  },
+  "devDependencies": {
+    "eslint": "7.20.0",
+    "eslint-plugin-json": "2.1.2"
+  }
+}
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