I have created a data action following the setup as mentioned here.

It fails with the below error:

{
  "message": "[Lambda error] The error returned from AWS indicates that you did not set your 'Request URL Template' to a AWS Lambda ARN. An example of a Lambda ARN is: 'arn:aws:lambda:us-east-1:123456789012:function:ProcessCallRecord'.    The specific error returned from AWS was:   Caused by: 1 validation error detected: Value 'https://someurl.execute-api.eu-central-1.amazonaws.com/test' at 'functionName' failed to satisfy constraint: Member must satisfy regular expression pattern: (arn:(aws[a-zA-Z-]*)?:lambda:)?([a-z]{2}((-gov)|(-iso([a-z]?)))?-[a-z]+-\\d{1}:)?(\\d{12}:)?(function:)?([a-zA-Z0-9-_\\.]+)(:(\\$LATEST|[a-zA-Z0-9-_]+))? (Service: Lambda, Status Code: 400, Request ID: 2b336bdb-168f-4b49-a016-11170652f2db) [05a40325-e47f-407a-8514-53f0f9a118d9]",
  "code": "bad.request",
  "status": 400,
  "entityName": "https://someurl.api.eu-central-1.amazonaws.com/test",
  "messageParams": {},
  "contextId": "05a40325-e47f-407a-8514-53f0f9a118d9",
  "details": [
    {
      "errorCode": "ACTION.REMOTE_ENDPOINT"
    }
  ],
  "errors": []
}