fix(tools): update error message for hints without tests (#64354)

Co-authored-by: Jessica Wilkins <67210629+jdwilkin4@users.noreply.github.com>
Co-authored-by: Huyen Nguyen <25715018+huyenltnguyen@users.noreply.github.com>

tools/challenge-parser/parser/plugins/add-tests.js

@@ -8,7 +8,9 @@ function plugin() {
   function transformer(tree, file) {
     const hintNodes = getSection(tree, '--hints--');
     if (hintNodes.length % 2 !== 0)
-      throw Error('Tests must be in (text, ```testString```) order');
+      throw Error(
+        'Hints must be in pairs: each hint text followed by a test code block'
+      );
 
     const tests = chunk(hintNodes, 2).map(getTest);
     file.data.tests = tests;

tools/challenge-parser/parser/plugins/add-tests.test.js

@@ -42,7 +42,7 @@ describe('add-tests plugin', () => {
   it('should throw if a test pair is out of order', () => {
     // TODO: update the markdown so it makes this error
     expect(() => plugin(brokenHintsAST, file)).toThrow(
-      'Tests must be in (text, ```testString```) order'
+      'Hints must be in pairs: each hint text followed by a test code block'
     );
   });