[BUG] Action.Http body with Input.Number trimmed

[fowl2]

Action.Http cuts off the first and last digit of the value of a Input.Number substitution.

It does this because StringWithSubstitutions::substituteInputValues() calls JSON.stringify(), then removes the first and last character:

AdaptiveCards/source/nodejs/adaptivecards/src/shared.ts

Lines 117 to 118 in 23b0987

	valueForReplace = JSON.stringify(valueForReplace);
	valueForReplace = valueForReplace.slice(1, -1);

Presumably it was written assuming the .value will always be a string and therefore be wrapped in double quotes, but in this case, it's a number, and the JSON numbers are unquoted.

For example, entering the number 12.34 will result in a JSON payload of "2.3".

Action.Http Snippet

"body": "{\"numberProperty\":\"{{aNumberInput.value}}\"}",

HTTP POST Body

{"numberProperty":"2.3"}"

Card JSON

{
  "type": "AdaptiveCard",
  "body": [
    {
      "type": "Input.Number",
      "id": "aNumberInput"
    },
    {
      "type": "ActionSet",
      "actions": [
        {
          "type": "Action.Http",
          "title": "Submit",
          "method": "POST",
          "url": "https://example.com",
          "body": "{\"numberProperty\":\"{{aNumberInput.value}}\"}",
          "headers": [
            {
              "name": "Authorization",
              "value": ""
            },
            {
              "name": "Content-Type",
              "value": "application/json"
            }
          ]
        }
      ]
    }
  ],
  "$schema": "http://adaptivecards.io/schemas/adaptive-card.json",
  "version": "1.0"
}

previously reported #5218

Version Tested: adaptivecards@.0.6