fix(sdk): Reports API: Better handling for summary metrics

[andrewtruong]

Description

• Fixes WB-NNNNN
• Fixes #NNNN

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

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

Testing

How was this PR tested?

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 75.84%. Comparing base (07f19a6) to head (02fcbff).
Report is 59 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #7669      +/-   ##
==========================================
+ Coverage   74.28%   75.84%   +1.55%     
==========================================
  Files         500      500              
  Lines       55658    54054    -1604     
==========================================
- Hits        41345    40996     -349     
+ Misses      13907    12649    -1258     
- Partials      406      409       +3     

Flag	Coverage Δ
func	41.40% <0.00%> (+0.03%)	⬆️
system	63.47% <0.00%> (-0.02%)	⬇️
unit	56.40% <100.00%> (+1.00%)	⬆️

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Files	Coverage Δ
wandb/apis/reports/v2/interface.py	86.83% <100.00%> (+0.02%)	⬆️

... and 106 files with indirect coverage changes