Connector builder server: Fail on failing tests

[flash1293]

Fixes #21197

By making sure the error from the python -m pytest command bubbles up correctly.

[lmossman]

Change LGTM.

But since the tests are currently failing, does that mean merging this will break CI? If so then we will need to fix those tests before merging this.
It seems like the tests are passing on the PR so I guess that is not the case? Was a fix already merged for the issue in the ticket that was causing the 8 test failures?

When I run the airbyte-connector-builder-server:airbytePythonDockerApply command on this branch, this is the output that I get:

==================================== ERRORS ====================================
_____ ERROR collecting connector_builder/impl/test_low_code_cdk_adapter.py _____
ImportError while importing test module '/home/unit_tests/connector_builder/impl/test_low_code_cdk_adapter.py'.
Hint: make sure your test modules/packages have valid Python names.
Traceback:
/usr/local/lib/python3.9/importlib/__init__.py:127: in import_module
    return _bootstrap._gcd_import(name[level:], package, level)
unit_tests/connector_builder/impl/test_low_code_cdk_adapter.py:13: in <module>
    from airbyte_cdk.sources.declarative.parsers.undefined_reference_exception import UndefinedReferenceException
E   ModuleNotFoundError: No module named 'airbyte_cdk.sources.declarative.parsers.undefined_reference_exception'
=========================== short test summary info ============================
ERROR unit_tests/connector_builder/impl/test_low_code_cdk_adapter.py
!!!!!!!!!!!!!!!!!!!! Interrupted: 1 error during collection !!!!!!!!!!!!!!!!!!!!
=============================== 1 error in 1.41s ===============================

> Task :airbyte-connector-builder-server:airbytePythonDockerApply FAILED

[flash1293]

The unit tests should have been fixed by #21107 , maybe this is a new problem that came in in between. Looking into this.

[flash1293]

Seems like there was a bad version of airbyte-cdk published (0.19) - pinning it to 0.18.1 for the connector-builder-server makes the build work on this PR. Let's wait for this to be resolved before merging this PR.

[flash1293]

An import path changed slightly, fixed that. Merging on green build.