Any of containers log not shipping to destination

[prashant-prajapati-ihsm]

I have tried the configuration shared in this repo,

As per the link given for fargate(https://github.com/aws-samples/amazon-ecs-firelens-examples/tree/mainline/examples/fluent-bit/config-file-type-file) I have write extra.conf and build fluentbit custom image by copying extra.conf in Dockerfile

I have attach extra.conf and Dockerfile below, you can review this.

But there is some problem in it or missing something, because When I tried this, any of my application container logs not shipping to datadog even stdout logs are also not shipping.
Can anybody do a review & suggest best possible solution or correct me if there is something wrong or missing anything in my approach.

NOTE: In my case destination is datadog & ${APP_LOG_FILE_PATH} will be set as environmental variable of container.

extra.conf

[SERVICE]
Flush 5
Grace 30
Daemon off

[INPUT]
Name tail
Tag app-logs
Buffer_Chunk_Size 1mb
Buffer_Max_Size 100mb
Mem_Buf_Limit 250mb
Path ${APP_LOG_FILE_PATH}
Refresh_Interval 5
Path_Key source
Skip_Empty_Lines true

[OUTPUT]
Name datadog
Match *
Host http-intake.logs.datadoghq.com
TLS on
compress gzip
apikey #apikey
dd_service datadog-logging
dd_source fluentbit-test
dd_message_key log

Dockerfile

FROM public.ecr.aws/aws-observability/aws-for-fluent-bit:stable
COPY ./extra.conf /fluent-bit/etc/extra.conf