Revisit tests for scripts in `buildSrc`

[myhau]

trafficstars

Tests for scripts in buildSrc require connection to the internet. This might be problematic in some cases (e.g. local compilation). Also, maven.org seems to be down from time to time and causes random test failures.

It's about ReleaseScriptsTest.

Related Slack threads:

• https://virtuslab.slack.com/archives/C0409GDKC06/p1673615559850639
• https://virtuslab.slack.com/archives/C0409GDKC06/p1669220628832459

Example test failures:

• https://github.com/VirtuslabRnD/pulumi-kotlin/actions/runs/3910239298/jobs/6682481259

[myhau]

The is not a huge problem anymore as we have retries. Let's try to mock Maven responses if the issue ever comes back.