Info log level too noisy in multitarget mode

What did you do?

I've set up Postgres Exporter to run in multitarget mode with a pgpass file for authentication

What did you expect to see?

Log messages at start time but not for every scrape

What did you see instead? Under which circumstances?

Three info log messages on every scrape

Environment

• System information:

  Linux 5.10.198-187.748.amzn2.aarch64 aarch64

• postgres_exporter version:

postgres_exporter, version 0.15.0 (branch: HEAD, revision: 68c176b8833b7580bf847cecf60f8e0ad5923f9a)
  build user:       root@7c5a76bc737a
  build date:       20231027-14:38:04
  go version:       go1.21.3
  platform:         linux/arm64
  tags:             unknown

• postgres_exporter flags:

    Args:
      --config.file=/etc/postgres_exporter.yml
      --web.listen-address=:9187
      --no-collector.database
      --no-collector.wal
    Environment:
      DATA_SOURCE_USER:  foo
      PGPASSFILE:        /postgres/.pgpass

• PostgreSQL version:

  13.12.0

• Logs:

postgres-exporter-64449bfc56-vcng4 prometheus-postgres-exporter ts=2023-12-05T18:23:18.938Z caller=probe.go:41 level=info msg="no auth_module specified, using default"
postgres-exporter-64449bfc56-vcng4 prometheus-postgres-exporter ts=2023-12-05T18:23:18.938Z caller=server.go:74 level=info msg="Established new database connection" fingerprint=foo.rds.amazonaws.com:5432
postgres-exporter-64449bfc56-vcng4 prometheus-postgres-exporter ts=2023-12-05T18:23:18.970Z caller=postgres_exporter.go:613 level=info msg="Semantic version changed" server=foo.rds.amazonaws.com:5432 from=0.0.0 to=13.12.0

Trace the repeated log messages in probe.go, server.go, and postgres_exporter.go while reproducing a multitarget scrape with the reported pgpass configuration. Done means startup information remains visible but the three info messages are not emitted on every scrape.