[import-profiler]: remove import-profiler skip workaround once Python 3.15 is officially released

[hebaalazzeh]

Context

A temporary skip was added to ci/run_single_test.sh ([]) for packages with heavy native/scientific dependencies (bigframes, pandas-gbq, google-cloud-documentai-toolbox, db-dtypes, bigquery-magics) that lack pre-built binary wheels on PyPI during Python 3.15 pre-releases.

Action Items

Once Python 3.15 is officially released and upstream binary wheels (numpy, pandas, pyarrow, etc.) are on PyPI:

• Remove UNSUPPORTED_PRE_RELEASE_PACKAGES from ci/run_single_test.sh.
• Verify import-profiler runs successfully across all packages.

Related PR

• Workaround PR: chore(ci): skip packages with unsupported pre-release deps in import profiler #18033
• Workflow: .github/workflows/import-profiler.yml
• Script: ci/run_single_test.sh