Metrics from spring batch are not pushed to prometheus push gateway - spring-batch

Question

I followed the approaches mentioned in this post. Basically I have my local prometheus and push gateway setup using docker from spring batch examples.
I have the below dependencies added in my build.gradle which means PrometheusPushGatewayManager bean is auto-configured and needs to push metrics to the gateway configured.
implementation("io.micrometer:micrometer-registry-prometheus:1.8.4")
implementation("io.prometheus:simpleclient_pushgateway:0.16.0")
My application.yml looks like below
metrics:
export:
prometheus:
enabled: true
pushgateway:
enabled: true
base-url: http://0.0.0.0:9091
job: main-job
push-rate: 5s
descriptions: true
But when I navigate to /metrics endpoint, the metrics are having values as 0.
example :
spring_batch_step_seconds_max{instance="",job="job",job_name="job-job-flow",name="process-5.csv",status="FAILED"} 0
spring_batch_step_seconds_max{instance="",job="job",job_name="job-job-flow",name="process-6.csv",status="COMPLETED"} 0
spring_batch_step_seconds_max{instance="",job="job",job_name="job-job-flow",name="process-7.csv",status="FAILED"} 0
spring_batch_step_seconds_max{instance="",job="job",job_name="job-job-flow",name="process-2csv",status="FAILED"} 0
spring_batch_step_seconds_max{instance="",job="job",job_name="job-job-flow",name="start-job-job",status="COMPLETED"} 0
I've checked this post, which indicates that we need to configure a registry but if I'm using the auto configured PrometheusPushGatewayManager by adding the simpleclient_pushgateway dependency, how to configure a registry ?
Keeping a breakpoint and viewing the value of Metrics.globalRegistry.meters[1] shows values like SampleImpl{duration(seconds)=392.074203242, duration(nanos)=3.92074203242E11, startTimeNanos=1098399187818886}. So they are captured but not pushed properly.
Am I missing something to configure for getting the metrics pushed properly to the gateway ?