Bug Report: cron.database_name is not dynamic; fixed to circle_test

[JalexChen]

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Describe the bug
POSTGRES_DB and the sample circle_test db in custom-postgresql.conf should be set to a variable, not hard coded as circle_test.

this would also apply to other options like listen addresses and shared_preload_libraries

As a result, even setting POSTGRES_DB to something, would not enable an extension like pg_cron, because it would only be enabled for circle_test

Expected behavior
changing POSTGRES_DB should also affect cron.database_name

Workarounds
editing the custom-postgresql.conf manually

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Additional context
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