Removed the unwanted character in Python code. (#1139)

Author: frankwwu

examples/Velocity.ipynb

@@ -20,7 +20,7 @@
     "# Set up for JupyterLite\n",
     "try:\n",
     "    import piplite\n",
-    "    await piplite.install(['ipyleaflet')\n",
+    "    await piplite.install('ipyleaflet')\n",
     "except ImportError:\n",
     "    pass"
    ]
@@ -122,7 +122,7 @@
    "name": "python",
    "nbconvert_exporter": "python",
    "pygments_lexer": "ipython3",
-   "version": "3.10.5"
+   "version": "3.10.11"
   }
  },
  "nbformat": 4,