Remove unnecessary coerceNumber property from autotickangles

Author: my-tien

src/plots/cartesian/layout_attributes.js

@@ -811,7 +811,6 @@ module.exports = {
     },
     autotickangles: {
         valType: 'data_array',
-        coerceNumber: true,
         dflt: [30, 90],
         editType: 'ticks',
         description: [

test/plot-schema.json

@@ -10700,7 +10700,6 @@
      "role": "object"
     },
     "autotickangles": {
-     "coerceNumber": true,
      "description": "When `tickangle` is set to *auto*, it will be set to the first angle in this array that is large enough to prevent label overlap.",
      "dflt": [
       30,
@@ -12055,7 +12054,6 @@
      "valType": "boolean"
     },
     "autotickangles": {
-     "coerceNumber": true,
      "description": "When `tickangle` is set to *auto*, it will be set to the first angle in this array that is large enough to prevent label overlap.",
      "dflt": [
       30,