feat(curriculum): prioritize showing index.jsx (#59100)

client/utils/sort-challengefiles.js

@@ -1,12 +1,12 @@
 exports.sortChallengeFiles = function sortChallengeFiles(challengeFiles) {
   const xs = challengeFiles.slice();
   xs.sort((a, b) => {
+    if (a.history[0] === 'index.jsx') return -1;
+    if (b.history[0] === 'index.jsx') return 1;
     if (a.history[0] === 'index.html') return -1;
     if (b.history[0] === 'index.html') return 1;
     if (a.history[0] === 'styles.css') return -1;
     if (b.history[0] === 'styles.css') return 1;
-    if (a.history[0] === 'index.jsx') return -1;
-    if (b.history[0] === 'index.jsx') return 1;
     if (a.history[0] === 'script.js') return -1;
     if (b.history[0] === 'script.js') return 1;
     if (a.history[0] === 'index.ts') return -1;

client/utils/sort-challengefiles.test.js

@@ -14,13 +14,13 @@ describe('sort-files', () => {
       expect(sorted.length).toEqual(expected.length);
     });
 
-    it('should sort the objects into html, css, jsx, js, ts order', () => {
+    it('should sort the objects into jsx, html, css, js, ts order', () => {
       const sorted = sortChallengeFiles(challengeFiles);
       const sortedKeys = sorted.map(({ fileKey }) => fileKey);
       const expected = [
+        'indexjsx',
         'indexhtml',
         'stylescss',
-        'indexjsx',
         'scriptjs',
         'indexts'
       ];