Choice options are updated incorrectly after fixing the value duplication error

[JaneSjs]

T19983 - Question Choices, duplicate values getting through, choices being formatted as number/string inconsistently.
https://surveyjs.answerdesk.io/internal/ticket/details/T19983

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To reproduce the issue, please open https://surveyjs.io/create-free-survey, add Checkboxes, and follow the screencast.

2024-09-25_11-56-07.mp4

The resultant survey JSON contains a duplicate "1" entries.

{
  "pages": [
    {
      "name": "page1",
      "elements": [
        {
          "type": "checkbox",
          "name": "question1",
          "choices": [
            "1",
            "1",
            "3"
          ]
        }
      ]
    }
  ]
}

Expected behavior the choices have 2, 1, 3 values and their display texts are updated correspondintly.

 "choices": [
       2, 
       1,
       3
]

[snlacks]

In the resulting JSON, one of the 1s is a string and one is a number, which might be why it's making the error message disappear.

{
  "pages": [
    {
      "name": "page1",
      "elements": [
        {
          "type": "checkbox",
          "name": "question1",
          "choices": [
            1,
            "1",
            "3"
          ]
        }
      ]
    }
  ]
}