errors on parsing (assert in DEBUG mode)

[skribtsov]

virtual json::reader::push_result json::reader::push(char): Assertion `this->length() - start_length == 1' failed.

my json is pretty simple

{
"kinesis": {
"kinesisSchemaVersion": "1.0",
"partitionKey": "filename_XXX_YYY_ZZZ_1214",
"sequenceNumber": "49639895790609468939184586116865187124815123996104196162",
"data": "MTVHCS9ob21lL0FubgoxNUcJdG90YWwK",
"approximateArrivalTimestamp": 1681668596.11
},
"eventSource": "aws:kinesis",
"eventVersion": "1.0",
"eventID": "shardId-000000000004:49639895790609468939184586116865187124815123996104196162",
"eventName": "aws:kinesis:record",
"invokeIdentityArn": "arn:aws:iam::780743977125:role/lambda-cpp-demo",
"awsRegion": "us-east-1",
"eventSourceARN": "arn:aws:kinesis:us-east-1:780743977125:stream/pawlin-datastream1"
}