Update WindNet to include Wind

[jacobbieker]

Pull Request

Description

Updates WindNet to actually use wind power as the target and as an input.

Fixes #

How Has This Been Tested?

Unit test

• [x] Yes

Checklist:

• [x] My code follows OCF's coding style guidelines
• [x] I have performed a self-review of my own code
• [x] I have made corresponding changes to the documentation
• [x] I have added tests that prove my fix is effective or that my feature works
• [x] I have checked my code and corrected any misspellings

[codecov[bot]]

Codecov Report

Attention: 2 lines in your changes are missing coverage. Please review.

Comparison is base (242064b) 77.84% compared to head (9a4313e) 78.26%. Report is 13 commits behind head on main.

Files	Patch %	Lines
ocf_datapipes/training/common.py	96.77%	1 Missing :warning:
ocf_datapipes/training/windnet.py	91.66%	1 Missing :warning:

Additional details and impacted files

```diff @@ Coverage Diff @@ ## main #262 +/- ## ========================================== + Coverage 77.84% 78.26% +0.41% ========================================== Files 120 121 +1 Lines 5465 5529 +64 ========================================== + Hits 4254 4327 +73 + Misses 1211 1202 -9 ```

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