Minor update docs instructions (#16609)

Author: tqchen

docs/conf.py

@@ -253,7 +253,7 @@ def install_request_hook(gallery_conf, fname):
 # you must request a Google Colab instance with a GPU by going to Runtime ->
 # Change runtime type -> Hardware accelerator -> GPU. If you wish to build from
 # source, see https://tvm.apache.org/docs/install/from_source.html
-pip install apache-tvm-cu113=={version} -f https://tlcpack.ai/wheels"""
+pip install apache-tvm-cu113=={version} --no-index  -f https://tlcpack.ai/wheels"""
 
 
 @monkey_patch("sphinx_gallery.gen_rst", "jupyter_notebook")