PERF: use StringHashtable in data algos

[jreback]

xref #16107

[codecov]

Codecov Report

Merging #16128 into master will decrease coverage by <.01%.
The diff coverage is 100%.

@@            Coverage Diff             @@
##           master   #16128      +/-   ##
==========================================
- Coverage   90.84%   90.83%   -0.01%     
==========================================
  Files         159      159              
  Lines       50774    50771       -3     
==========================================
- Hits        46124    46120       -4     
- Misses       4650     4651       +1

Flag	Coverage Δ
#multiple	88.61% <100%> (-0.01%)	⬇️
#single	40.33% <100%> (ø)	⬆️

Impacted Files	Coverage Δ
pandas/core/algorithms.py	94.41% <100%> (-0.03%)	⬇️
pandas/core/common.py	90.68% <0%> (-0.35%)	⬇️

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