fix(sweeps): Parse heartbeat run args using legacy agent

[hu-po]

Description

Fixes an issue where run.args coming from an AgentHeartbeat call were not formatted correctly for launch agents. Uses legacy sweep function to parse (to avoid code duplication).

Testing

How was this PR tested?

Checklist

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

[codecov]

Codecov Report

Merging #4180 (6c6d889) into master (70388b3) will increase coverage by 0.01%.
The diff coverage is 100.00%.

@@            Coverage Diff             @@
##           master    #4180      +/-   ##
==========================================
+ Coverage   82.68%   82.69%   +0.01%     
==========================================
  Files         256      256              
  Lines       32533    32534       +1     
==========================================
+ Hits        26899    26905       +6     
+ Misses       5634     5629       -5     

Flag	Coverage Δ
functest	55.01% <0.00%> (+0.01%)	⬆️
unittest	73.44% <100.00%> (-0.05%)	⬇️

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

Impacted Files	Coverage Δ
wandb/wandb_agent.py	20.52% <ø> (ø)
wandb/sdk/launch/sweeps/scheduler_sweep.py	98.63% <100.00%> (+0.01%)	⬆️
wandb/filesync/step_prepare.py	93.67% <0.00%> (-1.27%)	⬇️
wandb/sdk/lib/git.py	79.01% <0.00%> (-0.62%)	⬇️
wandb/sdk/internal/internal_api.py	86.46% <0.00%> (-0.52%)	⬇️
wandb/sdk/wandb_setup.py	88.44% <0.00%> (-0.51%)	⬇️
wandb/sdk/launch/agent/agent.py	92.25% <0.00%> (+0.70%)	⬆️
wandb/sdk/service/server_sock.py	92.89% <0.00%> (+1.01%)	⬆️
wandb/sdk/lib/sock_client.py	93.65% <0.00%> (+1.05%)	⬆️
wandb/integration/tensorboard/monkeypatch.py	90.12% <0.00%> (+2.46%)	⬆️
... and 1 more