NeptuneLogger ignores NEPTUNE_PROJECT environment variable
🐛 Bug
If project_name is not given, NeptuneLogger does not fetch the project name from the NEPTUNE_PROJECT environment variable and instead raises a neptune.api_exceptions.ProjectNotFound with the message "Project None not found".
To Reproduce
https://colab.research.google.com/gist/cifkao/70eb23d9021d8470b3208c7eb3607abd/the-boringmodel-neptune.ipynb
Expected behavior
The project name should be fetched from the NEPTUNE_PROJECT environment variable.
Environment

CUDA:

GPU:

Tesla T4


available:         True
version:           10.1


Packages:

numpy:             1.19.5
pyTorch_debug:     False
pyTorch_version:   1.8.1+cu101
pytorch-lightning: 1.2.6
tqdm:              4.41.1


System:

OS:                Linux
architecture:

64bit



processor:         x86_64
python:            3.7.10
version:           #1 SMP Thu Jul 23 08:00:38 PDT 2020