When using ECR as a source for AWS App Runner, the following "Health check on port XXXX" error occurred.

03-20-2022 07:18:52 AM [AppRunner] Health check on port '3000' failed. Service is rolling back. Check your configured port number. For more information, read the application logs.

Checking the "Application logs" as shown below,

the following was output:

exec user process caused: exec format error

The following Stack Overflow thread was found regarding this issue:

'exec user process caused: exec format error' in AWS Fargate Service
I am totally new to AWS but I've been running my dockerized application locally for months now with no issues. Now that I am trying to deploy this app via AWS ECS/Fargate, my containers are stopped
Stack Overflow

The thread contained the following answer:

docker buildx build --platform=linux/amd64 -t <image-name> .

After trying this, the deployment completed successfully.