Added missing dev dep

Author: erikras

package.json

@@ -40,6 +40,7 @@
     "@babel/plugin-syntax-dynamic-import": "^7.8.3",
     "@babel/plugin-syntax-import-meta": "^7.10.4",
     "@babel/plugin-transform-flow-strip-types": "^7.12.1",
+    "@babel/plugin-transform-react-jsx-source": "^7.12.13",
     "@babel/plugin-transform-runtime": "^7.12.1",
     "@babel/preset-env": "^7.12.1",
     "@babel/preset-flow": "^7.12.1",