@ABD NAY Thanks for reaching out.
This is the expected behavior for the HTTP trigger as this would be unique URL for your workflow that would be used to trigger your workflow. Once you have saved your workflow/deploy using ARM template it will generate the unique HTTP POST URL with the authentication that can be used for your application to call your workflow.
For more details on HTTP trigger please refer to this document.
Feel free to get back to me if you have any queries or concerns.