fix opensim conda package

Author: antoinefalisse

example.ipynb

@@ -58,7 +58,7 @@
         "!pip install -q condacolab\n",
         "import condacolab\n",
         "condacolab.install()\n",
-        "!conda install -c opensim-org opensim\n"
+        "!conda install -c opensim_admin opensim\n"
       ],
       "metadata": {
         "id": "QR8biTxkIEmC"