Add content_type to resource schema

Author: bdibon

samples/rum-events/resource-graphql.json

@@ -28,6 +28,7 @@
     "render_blocking_status": "non-blocking",
     "protocol": "HTTP/1.1",
     "delivery_type": "cache",
+    "content_type": "application/json",
     "graphql": {
       "operationType": "query",
       "operationName": "GetUserProfile",

samples/rum-events/resource.json

@@ -40,6 +40,7 @@
     },
     "protocol": "HTTP/1.1",
     "delivery_type": "cache",
+    "content_type": "application/json",
     "request": {
       "encoded_body_size": 512,
       "decoded_body_size": 1024,

schemas/rum/resource-schema.json

@@ -244,6 +244,11 @@
               "enum": ["cache", "navigational-prefetch", "other"],
               "readOnly": true
             },
+            "content_type": {
+              "type": "string",
+              "description": "Content type of the resource",
+              "readOnly": true
+            },
             "provider": {
               "type": "object",
               "description": "The provider for this resource",