Use plexus digraph in jaeger

[tiffon]

Which problem is this PR solving?

TraceGraph and TraceDiffGraph are still using the DirectedGraph component from plexus.

Short description of the changes

Changed TraceGraph and TraceDiffGraph to use Digraph.

Also, tweaked the visuals for TraceGraph a bit.

Before	After

[codecov]

Codecov Report

Merging #428 into master will decrease coverage by 0.18%.
The diff coverage is 55%.

@@            Coverage Diff             @@
##           master     #428      +/-   ##
==========================================
- Coverage   91.54%   91.36%   -0.19%     
==========================================
  Files         176      177       +1     
  Lines        4034     4040       +6     
  Branches      966      967       +1     
==========================================
- Hits         3693     3691       -2     
- Misses        297      306       +9     
+ Partials       44       43       -1

Impacted Files	Coverage Δ
...jaeger-ui/src/components/common/EmphasizedNode.tsx	0% <0%> (ø)
...onents/TraceDiff/TraceDiffGraph/TraceDiffGraph.tsx	90.9% <100%> (-0.76%)	⬇️
...src/components/TracePage/TraceGraph/TraceGraph.tsx	95% <100%> (ø)	⬆️
...components/TraceDiff/TraceDiffGraph/renderNode.tsx	85.71% <50%> (ø)
...-ui/src/components/TracePage/TraceGraph/OpNode.tsx	82.6% <60%> (-12.13%)	⬇️

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[everett980]

LGTM, assuming these two commits are the entirety of the diff.