chore: simplify eslint configuration (#44347)

* chore: extend import/recommended

* chore: use recommended lint rules

* refactor: apply lint rules

* chore: drop used config

client/plugins/fcc-source-challenges/create-challenge-nodes.js

@@ -31,7 +31,6 @@ function createChallengeNode(challenge, reporter) {
     type: challenge.challengeType === 7 ? 'CertificateNode' : 'ChallengeNode'
   };
 
-  /* eslint-disable prefer-object-spread/prefer-object-spread */
   return JSON.parse(
     JSON.stringify(
       Object.assign(

client/plugins/fcc-source-challenges/gatsby-node.js

@@ -29,7 +29,7 @@ exports.sourceNodes = function sourceChallengesSourceNodes(
   }
   const { createNode } = actions;
   const watcher = chokidar.watch(curriculumPath, {
-    ignored: /(^|[\/\\])\../,
+    ignored: /(^|[/\\])\../,
     ignoreInitial: true,
     persistent: true,
     usePolling: true,