Config the default locale for gradle as en_US

[penghuo]

Issue #, if available: #824

Description of changes:
Test in Linux with setting "LANG=ja_JP.UTF-8". The gradle will honer the configured setting en_US now.

By submitting this pull request, I confirm that my contribution is made under the terms of the Apache 2.0 license.

[codecov]

Codecov Report

Merging #847 (a401468) into develop (023f65a) will not change coverage.
The diff coverage is n/a.

@@            Coverage Diff             @@
##             develop     #847   +/-   ##
==========================================
  Coverage      99.85%   99.85%           
  Complexity      2102     2102           
==========================================
  Files            209      209           
  Lines           4678     4678           
  Branches         308      308           
==========================================
  Hits            4671     4671           
  Misses             5        5           
  Partials           2        2           

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