message: Don't build all variants for Windows CI
diff: @@ -27,9 +27,7 @@ cmake --version
  cd github\filament
  -:: If this is a continuous or release build, build all Filament static library
  -:: variants (/MD, /MDd, /MT, /MTd)
  -if "%KOKORO_JOB_TYPE%" == "CONTINUOUS_INTEGRATION" (set FILAMENT_BUILD_ALL_VARIANTS=1)
  +:: If this is a release build, build all Filament static library variants (/MD, /MDd, /MT, /MTd)
  if "%KOKORO_JOB_TYPE%" == "RELEASE" (set FILAMENT_BUILD_ALL_VARIANTS=1)
  if "%FILAMENT_BUILD_ALL_VARIANTS%" == "1" (
  