Switch to JSON .prettierrc

.prettierrc

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+{
+  "bracketSpacing": true,
+  "printWidth": 120,
+  "singleQuote": true,
+  "trailingComma": "es5",
+  "useTabs": false,
+  "plugins": ["prettier-plugin-solidity"],
+  "overrides": [
+    {
+      "files": "*.md",
+      "options": {
+        "parser": "markdown"
+      }
+    },
+    {
+      "files": "*.sol",
+      "options": {
+        "parser": "solidity-parse",
+        "printWidth": 80,
+        "tabWidth": 4,
+        "useTabs": false,
+        "singleQuote": false,
+        "bracketSpacing": false
+      }
+    }
+  ]
+}