ws-lambda-at-edge-generate-card-page causing 500

Hi,

I was trying followup this tutorial, but I'm failing at https://github.com/aws-samples/aws-lambda-edge-workshops/tree/master/Workshop1/Lab2_ContentGeneration#12-validate-the-function-works-in-lambda-console

The test returns 500 error with following message:

```
Response:
{
"status": "500",
"headers": {
"content-type": [
{
"value": "application/json"
}
],
"strict-transport-security": [
{
"value": "max-age=31536000; includeSubDomains"
}
],
"content-security-policy": [
{
"value": "default-src 'self'"
}
],
"x-xss-protection": [
{
"value": "1; mode=block"
}
],
"x-content-type-options": [
{
"value": "nosniff"
}
],
"x-frame-options": [
{
"value": "DENY"
}
]
},
"body": "{\n \"code\": \"ENOTFOUND\",\n \"errno\": \"ENOTFOUND\",\n \"syscall\": \"getaddrinfo\",\n \"hostname\": \"https://d32at75m0fmpm0.cloudfront.net\",\n \"host\": \"https://d32at75m0fmpm0.cloudfront.net\",\n \"port\": 443\n}"
}

Request ID:
"d6a29760-6816-46d5-a1f6-0a06314b3893"

Function Logs:
START RequestId: d6a29760-6816-46d5-a1f6-0a06314b3893 Version: $LATEST
2019-01-11T16:04:06.342Z d6a29760-6816-46d5-a1f6-0a06314b3893 Event: {
"Records": [
{
"cf": {
"config": {
"distributionDomainName": "https://d32at75m0fmpm0.cloudfront.net",
"distributionId": "E123EXAMPLE2",
"eventType": "origin-request"
},
"request": {
"clientIp": "2620:101:8030:74:9f2b:d246:c6e1:1d6a",
"headers": {
"user-agent": [
{
"key": "User-Agent",
"value": "Amazon CloudFront"
}
],
"host": [
{
"key": "Host",
"value": "alien-cards-be0359c0.s3.us-east-1.amazonaws.com"
}
]
},
"method": "GET",
"uri": "/card/da8398f4",
"querystring": ""
}
}
}
]
}
2019-01-11T16:04:06.380Z d6a29760-6816-46d5-a1f6-0a06314b3893 DynamoDB get params: {
"TableName": "AlienCards-7010b760",
"Key": {
"CardId": "da8398f4"
}
}
2019-01-11T16:04:06.402Z d6a29760-6816-46d5-a1f6-0a06314b3893 Couldn't fetch https://d32at75m0fmpm0.cloudfront.net/templates/card.html : getaddrinfo ENOTFOUND https://d32at75m0fmpm0.cloudfront.net https://d32at75m0fmpm0.cloudfront.net:443
2019-01-11T16:04:06.419Z d6a29760-6816-46d5-a1f6-0a06314b3893 response: {"status":"500","headers":{"content-type":[{"value":"application/json"}],"strict-transport-security":[{"value":"max-age=31536000; includeSubDomains"}],"content-security-policy":[{"value":"default-src 'self'"}],"x-xss-protection":[{"value":"1; mode=block"}],"x-content-type-options":[{"value":"nosniff"}],"x-frame-options":[{"value":"DENY"}]},"body":"{\n \"code\": \"ENOTFOUND\",\n \"errno\": \"ENOTFOUND\",\n \"syscall\": \"getaddrinfo\",\n \"hostname\": \"https://d32at75m0fmpm0.cloudfront.net\",\n \"host\": \"https://d32at75m0fmpm0.cloudfront.net\",\n \"port\": 443\n}"}
END RequestId: d6a29760-6816-46d5-a1f6-0a06314b3893
REPORT RequestId: d6a29760-6816-46d5-a1f6-0a06314b3893 Duration: 132.38 ms Billed Duration: 200 ms Memory Size: 128 MB Max Memory Used: 34 MB
```

When I'm opening https://d32at75m0fmpm0.cloudfront.net/templates/card.html in my browser, it returns the template, so I'm not sure what it is wrong.