Update path to transformers.js video and fix typo

Author: kfahn22

content/tracks/side-tracks/transformers-js/index.json

@@ -1,5 +1,5 @@
 {
   "title": "Transformers.js",
   "description": "A series exploring machine learning in JavaScript using Transformers.js! Learn how to run models hosted on Hugging Face directly in the browser with p5.js.",
-  "videos": ["transformers-js/introduction"]
+  "videos": ["transformers-js/introduction", "challenges/188-voice-chatbot"]
 }

content/videos/challenges/188-voice-chatbot/index.json

@@ -16,7 +16,7 @@
     "AI"
   ],
   "canContribute": true,
-  "relatedChallenges": ["42-markov-chain-name-generator", "c43-context-free-grammar", "80-voice-chatbot-with-p5speech"],
+  "relatedChallenges": ["42-markov-chain-name-generator", "43-context-free-grammar", "80-voice-chatbot-with-p5speech"],
   "timestamps": [
 
   ],
@@ -161,7 +161,7 @@
          {
            "icon": "🚂",
            "title": "What is Transformers.js",
-           "url": "https://www.youtube.com/watch?v=KR61bXsPlLU",
+           "url": "/tracks/transformers-js/transformers-js/introduction",
            "description": "In this video, I cover what Transformers.js is, how to load it into a p5.js sketch, explain the pipeline API, and demonstrate sentiment analysis and language detection examples."
          }