fix: resuming a run would overwrite image masks

[jacobromero]

Description

• Fixes WB-15237
• Fixes [App]: Initially logged image segmentation masks disappear after experiment is being resumed #6107

What does the PR do? Include a concise description of the PR contents.

When resuming a run, the image mask is not carried over to the new run config. This causes the original image to lose any image masks which it had.
This change adds masks/class_labels config key as one of the keys which should be copied over during run resume.

• I updated CHANGELOG.unreleased.md, or it's not applicable

Testing

How was this PR tested?

[codecov]

Codecov Report

Attention: Patch coverage is 91.30435% with 2 lines in your changes missing coverage. Please review.

Project coverage is 80.45%. Comparing base (2bef6be) to head (65c51bf).
Report is 87 commits behind head on main.

Files with missing lines	Patch %	Lines
wandb/sdk/internal/sender_config.py	0.00%	2 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #9592      +/-   ##
==========================================
+ Coverage   80.43%   80.45%   +0.01%     
==========================================
  Files         741      741              
  Lines       78840    78847       +7     
==========================================
+ Hits        63418    63438      +20     
+ Misses      14692    14676      -16     
- Partials      730      733       +3     

Flag	Coverage Δ
func	46.03% <75.00%> (-0.03%)	⬇️
system	64.94% <91.30%> (+0.12%)	⬆️
unit	65.30% <0.00%> (+0.02%)	⬆️

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

Files with missing lines	Coverage Δ
core/internal/runconfig/runconfig.go	93.20% <100.00%> (+1.46%)	⬆️
tests/system_tests/test_core/test_resume.py	100.00% <100.00%> (ø)
wandb/sdk/wandb_run.py	88.85% <ø> (+0.09%)	⬆️
wandb/sdk/internal/sender_config.py	76.31% <0.00%> (ø)

... and 12 files with indirect coverage changes

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[timoffex]

Solution LGTM, just some suggestions for writing a more maintainable test.