Update default variable settings name

[jmazanec15]

Issue #, if available:

Description of changes:
Update default variable settings name

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[codecov]

Codecov Report

Merging #209 into master will not change coverage.
The diff coverage is 100.00%.

@@            Coverage Diff            @@
##             master     #209   +/-   ##
=========================================
  Coverage     76.95%   76.95%           
  Complexity      302      302           
=========================================
  Files            50       50           
  Lines          1189     1189           
  Branches        100      100           
=========================================
  Hits            915      915           
  Misses          225      225           
  Partials         49       49           

Impacted Files	Coverage Δ	Complexity Δ
...ndistroforelasticsearch/knn/index/KNNSettings.java	83.47% <100.00%> (ø)	27.00 <0.00> (ø)
...relasticsearch/knn/index/KNNVectorFieldMapper.java	77.85% <100.00%> (ø)	15.00 <0.00> (ø)

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[vamshin]

LGTM!