Mongodb Exporter no metrics being collected for services added using collectors flag

User Impact:

Monitoring mongodb service using "--enable-all-collectors or --disable-collectors=topstats" and similar combination seems to be failing, hence can't monitor mongodb Service

STR:

1) Setup pmm-server 2.29.0

2) Setup pmm2-client 2.29.0

3) setup mongodb database and add it for monitoring using the following flags

pmm-admin add mongodb -port=27019 --agent-password='testing' --password=secret --username=pmm_mongodb --enable-all-collectors  -disable-collectors=topmetrics --service-name=mongodb_test_collections_flag --replication-set=rs0s

4) pmm-admin list returns the service, the status of the agent is running

5) check metrics, and dashboard for this service, no metrics are being collected, while it was expected to work

6) It seems we have a bug in log level too, even though the service is added with log-level default which is "warn" user can't see any error in pmm-agent logs

Logs are not available at all, hence can't share, I don't see any error on pmm-agent log on client node