remove bit about supporting non cubic boxes for now

docs/users/pdb_cookbook/index.ipynb

@@ -151,7 +151,7 @@
     "\n",
     "This PDB file comes from the [AMBER tutorial on making solvated simulations](https://ambermd.org/tutorials/basic/tutorial7/index.php). We have slightly modified the procedure to create a file suitable for loading into the OpenFF Toolkit:\n",
     "  * TIP3P water is used instead of OPC (a four-site model)\n",
-    "  * a cubic solvent box is used instead of an octohedron (though the Toolkit supports arbitrary triclinic boxes)\n",
+    "  * a cubic solvent box is used instead of an octohedron\n",
     "  * the N terminus of the protein is made neutral"
    ]
   },
@@ -316,7 +316,7 @@
    "name": "python",
    "nbconvert_exporter": "python",
    "pygments_lexer": "ipython3",
-   "version": "3.10.13"
+   "version": "3.11.4"
   },
   "widgets": {
    "application/vnd.jupyter.widget-state+json": {