message: fix colab research link
diff: @@ -126,7 +126,7 @@ landing_page:
  {% dynamic if request.tld == 'cn' %}
  <a href="https://github.com/tensorflow/tensorflow/blob/master/tensorflow/contrib/eager/python/examples/notebooks/eager_basics.ipynb" class="external">Eager execution basics</a>
  {% dynamic else %}
  - <a href="https://colab.sandbox.google.com/github/tensorflow/tensorflow/blob/master/tensorflow/contrib/eager/python/examples/notebooks/eager_basics.ipynb" class="external">Eager execution basics</a>
  + <a href="https://colab.research.google.com/github/tensorflow/tensorflow/blob/master/tensorflow/contrib/eager/python/examples/notebooks/eager_basics.ipynb" class="external">Eager execution basics</a>
  {% dynamic endif %}
  </li>
  <li>
  