chore(artifacts): allow setting artifact cache dir in wandb.init(...)

[dmitryduev]

Fixes WB-9581, WB-2620

Description

We recognize the WANDB_CACHE_DIR env var that can be used to change the directory where artifacts' cache lands. Here I added a cache_dir setting that if set in a wandb.init(...) call before wandb.sdk.interface.artifacts._artifacts_cache is initialized (with, e.g. a call to wandb.Artifact), will do the same.

Not sure if this is a good idea and would be fine with closing this PR :)

Testing

Added two unit tests.

Checklist

• Include reference to internal ticket "Fixes WB-NNNN" (and github issue "Fixes #NNNN" if applicable)

[codecov]

Codecov Report

Merging #3644 (1a84ab0) into main (e3cc081) will increase coverage by 20.46%.
The diff coverage is 100.00%.

❗ Current head 1a84ab0 differs from pull request most recent head d95e9cc. Consider uploading reports for the commit d95e9cc to get more accurate results

Additional details and impacted files

@@             Coverage Diff             @@
##             main    #3644       +/-   ##
===========================================
+ Coverage   62.83%   83.29%   +20.46%     
===========================================
  Files         281      280        -1     
  Lines       35303    34945      -358     
===========================================
+ Hits        22184    29109     +6925     
+ Misses      13119     5836     -7283     

Flag	Coverage Δ
functest	55.66% <100.00%> (+10.20%)	⬆️
unittest	73.97% <100.00%> (+21.03%)	⬆️

Flags with carried forward coverage won't be shown. Click here to find out more.

Impacted Files	Coverage Δ
wandb/sdk/interface/artifacts.py	79.15% <100.00%> (+11.18%)	⬆️
wandb/sdk/wandb_settings.py	94.48% <100.00%> (+6.93%)	⬆️
wandb/sdk/interface/message_future_poll.py	29.41% <0.00%> (-58.83%)	⬇️
wandb/sdk/interface/interface_grpc.py	60.98% <0.00%> (-5.02%)	⬇️
wandb/sdk/service/server_grpc.py	64.68% <0.00%> (-3.87%)	⬇️
wandb/sdk/launch/runner/gcp_vertex.py	90.09% <0.00%> (-0.91%)	⬇️
wandb/sdk/launch/runner/abstract.py	70.58% <0.00%> (-0.43%)	⬇️
wandb/sdk/launch/runner/aws.py	87.13% <0.00%> (-0.37%)	⬇️
wandb/errors/__init__.py	93.18% <0.00%> (-0.30%)	⬇️
wandb/sdk/launch/agent/agent.py	90.64% <0.00%> (-0.07%)	⬇️
... and 164 more

[dmitryduev]

hey @vwrj, mind weighing in? is this useful or should I just close this PR?

[dmitryduev]

Converting to a draft for now.