docs: fix typo

[mmaitre314]

docs: replace thier -> their

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[mhamilton723]

/azp run

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[codecov]

Codecov Report

Merging #990 (4635d64) into master (062a470) will decrease coverage by 0.10%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##           master     #990      +/-   ##
==========================================
- Coverage   84.96%   84.85%   -0.11%     
==========================================
  Files         196      196              
  Lines        9116     9116              
  Branches      577      577              
==========================================
- Hits         7745     7735      -10     
- Misses       1371     1381      +10     

Impacted Files	Coverage Δ
...a/com/microsoft/ml/spark/io/http/HTTPClients.scala	56.66% <0.00%> (-16.67%)	⬇️

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