Dialog unit tests fail on OSX

[marshall-mcmullen]

For some reason, the arrow keys do not work from unit tests on OSX even though they work fine in the actual product.

For example, I log the raw characters the test is sending:

[2021-06-21T16:19:48Z] Input
2417
^[OBLocke^[OBHobbes$
2418
^I$
2419
$

Yet when we process those characters, we DO see the correct arrow key, yet dialog interprets it as ENTER incorrectly:

[2021-06-21T16:19:49Z|dialog.sh:651:dialog_prompt] [Sending] ^[OB$
chr DLGK_ENTER (ch=0x21d, fkey=541)
# dlg_result_key(dialog_key=541, fkey=541)
# dlg_ok_buttoncode(1) = 3:EXTRA

To unblock current work, I've added a skip_if "os darwin" to the affected failing tests:

      ETEST_dialog_yesno_no
      ETEST_dialog_prompt_optional_multi_first
      ETEST_dialog_prompt_optional_multi_middle
      ETEST_dialog_prompt_default_values_override
      ETEST_dialog_prompt_default_values_override_tab
      ETEST_dialog_prompt_default_values_override_tab_term
      ETEST_dialog_checklist
      ETEST_dialog_checklist_middle
      ETEST_dialog_checklist_spaces
      ETEST_dialog_radiolist
      ETEST_dialog_radiolist_middle
      ETEST_dialog_radiolist_spaces