Enable xthi and ythi unit tests for win32.

[KineticTheory]

Background

• Previously, xthi and ythi were updated to allow compilation under Visual Studio. However, the unit tests associated with these binaries were not enabled.

Purpose of Pull Request

• Enable unit tests c4_tst[XY]thi_[12].

Status

• Reference:
  • Pre-Merge Code Review
  • CDash Status
• Checks
  • Travis CI checks pass
  • Code coverage does not decrease
  • Valgrind test passes
  • Toss3 checks pass
  • Trinitite checks pass
  • Code reviewed/approved, sufficient DbC checks, testing, documentation

[codecov]

Codecov Report

Merging #558 into develop will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           develop    #558   +/-   ##
=======================================
  Coverage     93.3%   93.3%           
=======================================
  Files          377     377           
  Lines        17677   17677           
=======================================
  Hits         16497   16497           
  Misses        1180    1180

[KineticTheory]

@clevelam This is ready for your review and merge.

[clevelam]

LGTM