Fixed date type var bug

[Snaipergelka]

Type of change

Please delete options that are not relevant.

• Bug fix (non-breaking change which fixes an issue)

Fixed bug with date time and date types of reflex.Var.

Added check_type_in_var_is_string_type function that checks if value type in global set StringVarType of types that should be used as a string literal and then sets _var_is_string=true.

If there will be a need to add more types that should be considered as strings, just add them in set StringVarType.

Seems that it solves the problem.

Closes #3235

[benedikt-bartscher]

@Snaipergelka StringVarType is not adjustable by users if i am not mistaken.
If users can define their own serializers, they should also be able to inform reflex that smth is serialized as a string.
Take a look at my related pr: #3227

[Snaipergelka]

@Snaipergelka StringVarType is not adjustable by users if i am not mistaken. If users can define their own serializers, they should also be able to inform reflex that smth is serialized as a string. Take a look at my related pr: #3227

@benedikt-bartscher yes, StringVarType is not adjustable by users. It is rather a hot fix for dates and date times (and other types if needed) to mark them as strings without additional information from user.

I guess your solution is more wide.

[masenf]

Thank you for the contribution 🙏 .

We will ultimately take the more generic fix in #3227 to address this issue.

@Snaipergelka please feel free to review or make comments over there.