Remove NeptuneLogger integration from PyTorch Lightning (#21572)
* Remove NeptuneLogger integration from PyTorch Lightning
- Deleted NeptuneLogger from the logger initialization and related files.
- Updated documentation and tests to reflect the removal of NeptuneLogger.
- Adjusted logger-related code to ensure compatibility without NeptuneLogger.
* keep `NeptuneLogger` class as a wrapper and raise an error suggesting litlogger instead
* update
* update
* Update src/lightning/pytorch/loggers/neptune.py
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Co-authored-by: Bhimraj Yadav <bhimrajyadav977@gmail.com>
Co-authored-by: Justus Schock <12886177+justusschock@users.noreply.github.com>