update schema

Author: emilykl

test/plot-schema.json

@@ -9955,6 +9955,12 @@
     "editType": "legend",
     "valType": "boolean"
    },
+   "sketchmode": {
+    "description": "Determines whether the plot should be rendered with sketch-style appearance. When set to `true`, plot elements will have a hand-drawn, sketchy look.",
+    "dflt": false,
+    "editType": "plot",
+    "valType": "boolean"
+   },
    "sliders": {
     "items": {
      "slider": {