tests: 📏 add smoke tests

[duyifanict]

sloved #285

[Copilot]

Pull Request Overview

This PR adds a smoke test for the DLinear model along with a minimal test dataset and updates the CI workflow to support running these tests.

• Adds smoke test for DLinear model (test_dlinear_smoke_test)
• Introduces ETTh1_mini dataset for testing (train/val/test splits with timestamps)
• Updates GitHub Actions workflow to install PyTorch and run all pytest tests
• Removes obsolete test files (run_all_test.py and test_launcher.py)

Reviewed Changes

Copilot reviewed 5 out of 14 changed files in this pull request and generated 2 comments.

Show a summary per file

File	Description
tests/smoke_test/test_dlinear.py	New smoke test for DLinear model using ETTh1_mini dataset
tests/smoke_test/datasets/ETTh1_mini/*.npy	Binary NumPy files containing test data and timestamps
tests/smoke_test/datasets/ETTh1_mini/meta.json	Metadata configuration for the ETTh1_mini dataset
.gitignore	Updated to explicitly include test dataset files
.github/workflows/python-test.yml	Added PyTorch installation and removed pytest ignore flag
tests/run_all_test.py	Removed obsolete test runner
tests/basicts_test/test_launcher.py	Removed empty test placeholder

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[Copilot]

Invalid JSON syntax: NaN is not a valid JSON value. It should be either null, a number, a string like \"NaN\", or removed if not needed. JSON parsers will fail to parse this file.

Suggested change

	"null_val": NaN
	"null_val": null

[Copilot]

The installation of torchvision appears unnecessary for this test suite as the smoke test only imports and uses PyTorch core functionality. Consider removing torchvision to reduce installation time and dependencies.

Suggested change

	pip install torch torchvision --index-url https://download.pytorch.org/whl/cpu
	pip install torch --index-url https://download.pytorch.org/whl/cpu