add modified property to video panel schema

Author: IshavSohal

StorylinesSchema.json

@@ -281,6 +281,10 @@
                 "type": {
                     "type": "string",
                     "enum": ["video"]
+                }, 
+                "modified": {
+                    "type": "boolean",
+                    "description": "An optional tag that specifies whether the panel has been modified from its default configuration"
                 }
             },
             "required": ["src", "type"]

public/StorylinesSlideSchema.json

@@ -358,6 +358,10 @@
                 "customStyles": {
                     "type": "string",
                     "description": "Additional CSS styles to apply to the panel."
+                }, 
+                "modified": {
+                    "type": "boolean",
+                    "description": "An optional tag that specifies whether the panel has been modified from its default configuration" 
                 }
             },
             "additionalProperties": false,