Optimize heartbeat timeout judgement if worker already succeeded.

[BalaBalaYi]

What changes were proposed in this pull request?

1. Add 'succeeded report' implement.
2. Add 'succeeded' flag for Node object.
3. Skip 'succeeded node' in 'noheartbeat' judgement.

Why are the changes needed?

Won't trigger heartbeat timeout if agent already succeeded exit.

Does this PR introduce any user-facing change?

Specify whether this pull request introduces any changes that users will directly interact with or notice.

How was this patch tested?

Ut and training job.

[codecov]

Codecov Report

Attention: Patch coverage is 96.15385% with 2 lines in your changes missing coverage. Please review.

Project coverage is 80.34%. Comparing base (cfbc24b) to head (8f95c81).
Report is 1 commits behind head on master.

Files with missing lines	Patch %	Lines
dlrover/python/tests/test_job_manager.py	90.47%	2 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #1289      +/-   ##
==========================================
+ Coverage   80.30%   80.34%   +0.04%     
==========================================
  Files         222      222              
  Lines       20429    20481      +52     
==========================================
+ Hits        16405    16456      +51     
- Misses       4024     4025       +1     

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