Add edge segment size to filter out change points that are observed on the data edge

[AnandInguva]

Workaround for #28757.

When a change point is observed on the edge sometimes, we can discard it because it will still be alerted but after the edge_segment_size runs.

Fixes: #28757

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[codecov]

Codecov Report

Merging #28780 (c72b47d) into master (31e1c7a) will decrease coverage by 0.03%.
Report is 36 commits behind head on master.
The diff coverage is 12.50%.

@@            Coverage Diff             @@
##           master   #28780      +/-   ##
==========================================
- Coverage   72.23%   72.21%   -0.03%     
==========================================
  Files         684      685       +1     
  Lines      101198   101518     +320     
==========================================
+ Hits        73102    73307     +205     
- Misses      26518    26633     +115     
  Partials     1578     1578              

Flag	Coverage Δ
python	82.70% <12.50%> (-0.10%)	⬇️

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Files	Coverage Δ
.../python/apache_beam/testing/analyzers/constants.py	100.00% <100.00%> (ø)
...ache_beam/testing/analyzers/perf_analysis_utils.py	18.44% <0.00%> (-3.35%)	⬇️

... and 16 files with indirect coverage changes

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[tvalentyn]

I would move this logic into find_latest_change_point_index since there are other considerations in that function to filter out noise.

[tvalentyn]

you could also skip adding extra param to find_latest_change_point_index until we have a usecase to customize it with a non-default value.

[AnandInguva]

Done

[tvalentyn]

should we be considering prior change_points_indices? That is, instead of returning change_points_indices[-1], we return the latest change point that is not in the edge segment.

[AnandInguva]

I think we should return the latest change point itself. Even if we ignore it for example 3 days, it gets filed.

We also ignore change points that are occurred 14 days before. Most often change_points_indices[-2] lies outside of that window or doesn't exist. So we could just follow the current approach.

[tvalentyn]

ok. yes, i think it should get file eventually.