remove MACPYTHON_DEFAULT_OSX logic from test_multibuild.sh and travis_osx_steps.sh

tests/test_multibuild.sh

@@ -8,9 +8,7 @@ source tests/test_common_utils.sh
 source tests/test_fill_submodule.sh
 if [ -n "$IS_OSX" ]; then
     source osx_utils.sh
-    # osx_utils defines MACPYTHON_DEFAULT_OSX
-    MB_PYTHON_OSX_VER=${MB_PYTHON_OSX_VER:-$MACPYTHON_DEFAULT_OSX}
-    get_macpython_environment $PYTHON_VERSION $MB_PYTHON_OSX_VER $VENV
+    get_macpython_environment $PYTHON_VERSION {$MB_PYTHON_OSX_VER:-""} $VENV
     source tests/test_python_install.sh
     source tests/test_fill_pyver.sh
     source tests/test_fill_pypy_ver.sh

travis_osx_steps.sh

@@ -9,8 +9,6 @@ ENV_VARS_PATH=${ENV_VARS_PATH:-env_vars.sh}
 
 # These load common_utils.sh
 source $MULTIBUILD_DIR/osx_utils.sh
-# osx_utils defines MACPYTHON_DEFAULT_OSX
-MB_PYTHON_OSX_VER=${$MB_PYTHON_OSX_VER:-$MACPYTHON_DEFAULT_OSX}
 if [ -r "$ENV_VARS_PATH" ]; then source "$ENV_VARS_PATH"; fi
 source $MULTIBUILD_DIR/configure_build.sh
 source $MULTIBUILD_DIR/library_builders.sh
@@ -23,7 +21,7 @@ function before_install {
     brew cask uninstall oclint || true    
     export CC=clang
     export CXX=clang++
-    get_macpython_environment $MB_PYTHON_VERSION $MB_PYTHON_OSX_VER venv
+    get_macpython_environment $MB_PYTHON_VERSION ${MB_PYTHON_OSX_VER:-""} venv
     source venv/bin/activate
     pip install --upgrade pip wheel
 }