[infra] Add configurable log level for CI test runs

[XL-Zhao-23]

[infra] Add configurable log level for CI test runs

Linked issue: #96

Purpose of change

Improve observability of CI test runs by making log levels configurable through environment variables. This allows enabling INFO level logging in CI workflows for debugging purposes while keeping local test runs quiet by default.

Tests

• Modified log4j2-test.properties in runtime and e2e-test modules to support LOG_LEVEL environment variable
• Updated .github/workflows/ci.yml to set LOG_LEVEL=INFO for Java tests, Java IT, and e2e tests
• Default behavior remains unchanged (OFF) when environment variable is not set

API

No public API changes.

Documentation

• doc-not-needed

[XL-Zhao-23]

This CI not passing could be due to network instability.

[wenjin272]

Hi, @XL-Zhao-23, thanks for your contribution. Since currently we don't have too many test cases, I think printing the log to screen is acceptable.

Can we also print the log for python test either?

[XL-Zhao-23]

Thanks for the suggestion!
Python tests now support configurable log levels: CI runs output INFO logs (via LOG_LEVEL: INFO in .github/workflows/ci.yml) while local runs remain quiet by default (CRITICAL), configurable with export LOG_LEVEL=INFO.
The tools/ut.sh script passes this to pytest via -o log_cli=true -o log_cli_level=${LOG_LEVEL:-CRITICAL}, keeping behavior consistent with Java tests and avoiding pyproject.toml schema issues.

[wenjin272]

LGTM. Could you take a look at your convenient @xintongsong ?

[xintongsong]

Ported to release-0.2 in 270fa95.