Issue#38 Add targeted MySQL↔BigQuery CI coverage

[kantselovich]

Fixes #38

[orca-security-us]

Orca Security Scan Summary

Status	Check	Issues by priority
Passed	Infrastructure as Code	0   0   0   0	View in Orca
Passed	SAST	0   0   0   0	View in Orca
Passed	Secrets	0   0   0   0	View in Orca
Passed	Vulnerabilities	0   0   0   0	View in Orca

[gemini-code-assist]

Code Review

This pull request updates the BigQuery database connector to automatically configure a default dataset in the query job configuration and adds BigQuery-related environment variables to the development environment file. Feedback includes a recommendation to safely handle the query job configuration to avoid potential TypeErrors when overlapping with keyword arguments, and a suggestion to use placeholders in the environment file instead of hardcoded local paths and project IDs to improve portability.

[gemini-code-assist]

Passing default_query_job_config as an explicit keyword argument while it might also be present in **kw will cause a TypeError (multiple values for argument) if a user provides it in the connection parameters. It is safer to pop it from kw and then configure it.

Suggested change

	default_config = bigquery.QueryJobConfig(default_dataset=f"{project}.{dataset}")
	self._client = bigquery.Client(project=project, credentials=credentials, default_query_job_config=default_config, **kw)
	default_config = kw.pop("default_query_job_config", bigquery.QueryJobConfig())
	default_config.default_dataset = f"{project}.{dataset}"
	self._client = bigquery.Client(project=project, credentials=credentials, default_query_job_config=default_config, **kw)

[gemini-code-assist]

Hardcoding specific project IDs (dms-analytics-v2-data-diff) and local file paths for credentials (bq.sa) in a shared environment file reduces portability and can lead to configuration issues for other contributors. It is recommended to use placeholders or provide a .env.example file instead.