fix: typo on path to colab notebook (#129)

Author: andreatgretel

docs/overrides/main.html

@@ -10,7 +10,7 @@
 {% block content %}
 {% if page.nb_url %}
   <div data-md-component="latest-only" style="display: none;">
-    <a target="_blank" href="https://colab.research.google.com/github/NVIDIA-NeMo/DataDesigner/tree/main/docs/colab_notebooks/{{ page.nb_url.split('/')[-1] }}">
+    <a target="_blank" href="https://colab.research.google.com/github/NVIDIA-NeMo/DataDesigner/blob/main/docs/colab_notebooks/{{ page.nb_url.split('/')[-1] }}">
       <img src="https://colab.research.google.com/assets/colab-badge.svg" alt="Open In Colab"/>
     </a>
     <script>