fix(tests): resolve uncollected weather tests and correct assertions (#161)

[vaaiiibbhav]

Related Issue / Discussion:

Fixes Issue #161

Changes:

Please list the central functionalities that have been changed:

• Modified tests/test_weather.py

Further Details:

Summary:

• Motivation: The test infrastructure for the WeatherCond class (get_u() and get_v() methods) was completely broken and omitted during test collection.
• Before:
  • Test functions lacked the test_ prefix, preventing pytest from discovering them.
  • Parameter counts in @pytest.mark.parametrize did not match the function signatures.
  • Assertions were self-referential (e.g., checking if a variable equaled itself) or mathematically incorrect regarding the inverse logic for test_theta_from_uv.
• After:
  • Renamed functions to follow proper test_ prefixes.
  • Aligned function signatures with the parametrized decorators (u_res / v_res).
  • Implemented proper value checks utilizing pytest.approx() and updated the test data (windspeed = np.sqrt(2)) to ensure mathematical accuracy. Total active passing tests in this file increased from 4 to 12.

Dependencies:

No new dependencies are required for this modification.

PR Checklist:

In the context of this PR, I:

• have (already previously) filled the 52North Contributor License Agreement and received positive feedback on this matter
• have filled the 52North Contributor License Agreement and am waiting for feedback
• provide unit tests embedded in the WRT test framework (WeatherRoutingTool/tests) that allow the simple testing of the new/modified functionalities. All (previous and new) unit tests execute without new error messages.
• ensure that the code formatter runs without errors/warnings
• ensure that my changes follow the WRT’s guidelines for contributing at the time of the contribution