Investigate why TeamCity Oracle builds so slow

[bahusoid]

Oracle teamcity tests take 40 minutes to finish. Doesn't look right - if I remember correctly it was about 20 minutes some months/years back. I wonder if #1511 is a culprit (as first Oracle related change for TeamCity committed after #1517)

[hazzik]

It was 20 minutes before we added async tests. Then it became around ~35 minutes.

[bahusoid]

before we added async tests. Then it became around ~35 minutes.

I don't think it's true... See here #1517 (review)
This PR includes async tests and Oracle build took 21 minutes (async tests were added in 5.0, this PR for 5.1. Also see Async folder is already present).

[hazzik]

Probably was not enough resources on the build server. Now build takes ~26 minutes

[bahusoid]

Probably was not enough resources on the build server. Now build takes ~26 minutes

Yet it took 20 minutes with old configuration sometime ago (async tests included).