source-postgres: improve test setup and teardown to make them faster

[alafanechere]

Java tests (unit / integration) rely on services like Debezium and testcontainers. A lot of runtime is spent waiting for these services to be available. E.G: in unit tests wait 1mn for debezium to start. For testcontainers: a lot of database containers are started (one by test): it’s resource intensive and might be optimizable with clever container reuse.

Furthermore, in Java tests, a lot of tests are effectively skipped by early exits, because those tests are defined in connector-agnostic base classes. However, we still pay the price of doing setups and teardowns.

Finally, on CAT very simple tests like spec take a couple of minutes to run. This can be due to a CAT daggerization overhead

[alafanechere]

Finally, on CAT very simple tests like spec take a couple of minutes to run. This can be due to a CAT daggerization overhead

This is addressed in #31699 and had a specific issue #31703

[postamar]

See #31298 for profiling results.

[postamar]

#31818 covers the testcontainers aspect of this issue and is the only outstanding thing remaining here.

[bnchrch]

@postamar Just wanted to checkin if this is able to be considered done and closed?

[postamar]

Oh yes!