docs: update stock_field_overrides to keep the ordering consistent (#227)

This confused a customer who happened to apply these exact same
overrides for severity_v2.

Author: shivansh

fern/docs/pages/customization.mdx

@@ -430,22 +430,22 @@ curl --location 'https://api.devrev.ai/internal/schemas.custom.set' \
       "uenum_values": [
         {
           "id": 1,
-          "label": "Low",
+          "label": "Blocker",
           "ordinal": 1
         },
         {
           "id": 2,
-          "label": "Medium",
+          "label": "High",
           "ordinal": 2
         },
         {
           "id": 3,
-          "label": "High",
+          "label": "Medium",
           "ordinal": 3
         },
         {
           "id": 4,
-          "label": "Blocker",
+          "label": "Low",
           "ordinal": 4
         }
       ],