[C][Client] Allocate memory for the element of array when the type is number

Created by: ityuhui

If the type of element of an array is number, e.g.

        "supplementalGroups": {
          "description": "A list of groups applied to the first process run in each container, in addition to the container's primary GID.  If unspecified, no groups will be added to any container.",
          "items": {
            "format": "int64",
            "type": "integer"
          },
          "type": "array"
        },

The current template code of CLibcurl will not allocate memory for the element before adding it to a list:

    list_addElement(supplemental_groupsList , &supplemental_groups_local->valuedouble);

supplemental_groups_local is a local variable, it will be released soon. And then the pointer pointing to supplemental_groups_local->valuedouble will be invalid.

This PR allocates memory for the element:

    double *supplemental_groups_local_value = (double *)calloc(1, sizeof(double));
    if(!supplemental_groups_local_value)
    {
        goto end;
    }
    *supplemental_groups_local_value = supplemental_groups_local->valuedouble;
    list_addElement(supplemental_groupsList , supplemental_groups_local_value);

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Hi @wing328 @zhemant @michelealbano

Could you please review this PR ? Thanks.