Improve get trace name performance

[everett980]

Which problem is this PR solving?

• Closes Support loading traces with large number of spans. #562
• Reduces execution time of getTraceName for a trace with 11.5k spans from 20s to 250ms

Short description of the changes

• Replace reduce of spans into allTraceSpans with a set of allIDs
• Replace multiple loops with a single for loop
• Memoization remains beneficial as it improves the render time of the gantt chart and other trace views by 3x (from 750ms to 250ms for test trace).

[codecov]

Codecov Report

Merging #574 into master will increase coverage by 0.04%.
The diff coverage is 100.00%.

@@            Coverage Diff             @@
##           master     #574      +/-   ##
==========================================
+ Coverage   89.92%   89.97%   +0.04%     
==========================================
  Files         214      214              
  Lines        5221     5225       +4     
  Branches     1334     1338       +4     
==========================================
+ Hits         4695     4701       +6     
+ Misses        483      481       -2     
  Partials       43       43              

Impacted Files	Coverage Δ
packages/jaeger-ui/src/model/trace-viewer.tsx	100.00% <100.00%> (ø)
...eViewer/TimelineHeaderRow/TimelineViewingLayer.tsx	91.52% <0.00%> (+3.38%)	⬆️

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[yurishkuro]

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