Plugin Support

...G...... [ZBX-23719] add duplicate flag handling

* commit '5ca691867d56df7243147fec53dc6fd7bfaad85f':
  ...G...... [ZBX-23719] add test string flag reverse order test case
  ...G...... [ZBX-23719] fix error msg, add test cases
  ...G...... [ZBX-23719] add duplicate flag handling

(cherry picked from commit 386e8facc213ce70a1377daba32f709d29f76538)