Remove internal metrics in favor of torchmetrics

[Borda]

This PR is resolving #4283

Still some open questions/tasks:

• shall it be hard removal or with deprecation warning to not breaking user experience (as it is now in this draft)
• shall be TorchMetrics install or full_install dependency

[codecov]

Codecov Report

Merging #4287 (91ce15e) into master (a581be6) will decrease coverage by 0.19%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##           master    #4287      +/-   ##
==========================================
- Coverage   82.47%   82.28%   -0.20%     
==========================================
  Files         311      310       -1     
  Lines       15941    15877      -64     
==========================================
- Hits        13148    13065      -83     
- Misses       2793     2812      +19     

Impacted Files	Coverage Δ
torch_geometric/utils/__init__.py	100.00% <ø> (ø)
torch_geometric/nn/conv/utils/typing.py	81.25% <0.00%> (-17.50%)	⬇️
torch_geometric/io/tu.py	93.58% <0.00%> (-2.57%)	⬇️
torch_geometric/graphgym/utils/io.py	78.04% <0.00%> (-2.44%)	⬇️
torch_geometric/nn/models/mlp.py	98.41% <0.00%> (-1.59%)	⬇️
torch_geometric/transforms/gdc.py	77.94% <0.00%> (-1.03%)	⬇️
torch_geometric/nn/conv/rgat_conv.py	83.76% <0.00%> (-0.53%)	⬇️
torch_geometric/graphgym/config.py	94.52% <0.00%> (-0.50%)	⬇️
torch_geometric/graphgym/utils/comp_budget.py	15.51% <0.00%> (+0.51%)	⬆️

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[Borda]

@rusty1s seems that this PR a slightly lowering the code coverage but it is quite understandable...

[Borda]

@rusty1s may I get your opinion on this suggestion/change as the PR description: 🐰

• hard removal or with deprecation warning to not breaking user experience (as it is now in this draft)
• TorchMetrics install or full_install dependency

[rusty1s]

@Borda Yes, sorry for the delay :)

• I think torchmetrics should be a dependency of the full_install.
• I'm fine with a hard removal TBH since I doubt that these are functions that most PyG users are actively using. If we go for a deprecation warning, is there any chance we can make use of the in-house deprecated warning rather than relying on the external dependency?

[Borda]

I'm fine with a hard removal TBH since I doubt that these are functions that most PyG users are actively using.

this is something I also do not know that is why I started wth soft removal and can be dropped completely in net release... but happy to follow any your suggestion :)

• If we go for a deprecation warning, is there any chance we can make use of the in-house deprecated warning rather than relying on the external dependency?

sure I was using a deprecation package I know, but happy to use any according to your suggestion :)

[rusty1s]

Let's go for hard removal :)

[Borda]

Let's go for hard removal :)

Done 👍