[JENKINS-58826] Fix visible number of build results in charts

[uhafner]

See JENKINS-58826.

The number of builds which are included into a trend chart is currently limited by the fixed number of 50 builds. This limit is currently only working correctly in single trend charts. In aggregations (and charts with days as domain axis), this limit is applied on the wrong side, i.e. the charts are showing the first 50 builds and not the last 50 builds.

[codecov]

Codecov Report

Merging #226 into master will not change coverage.
The diff coverage is 100%.

@@            Coverage Diff            @@
##             master     #226   +/-   ##
=========================================
  Coverage     82.68%   82.68%           
  Complexity     1582     1582           
=========================================
  Files           247      247           
  Lines          5411     5411           
  Branches        388      388           
=========================================
  Hits           4474     4474           
  Misses          786      786           
  Partials        151      151

Impacted Files	Coverage Δ	Complexity Δ
.../plugins/analysis/core/charts/CompositeResult.java	76.66% <100%> (ø)	4 <0> (ø)	⬇️

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