Add Validation Method code fix doesn't account for body-less declarations

[SteveDunn]

Describe the bug

Given:
public partial readonly struct RedemptionId;, when I alt+enter and do 'Add Validation Method', I get:

[ValueObject<string>]
public readonly partial struct RedemptionId private static Validation Validate(string input)
{
    bool isValid = true; // todo: your validation
    return isValid ? Validation.Ok : Validation.Invalid("[todo: describe the validation]");
};

Steps to reproduce

Given:
public partial readonly struct RedemptionId;, when I alt+enter and do 'Add Validation Method', I get:

[ValueObject<string>]
public readonly partial struct RedemptionId private static Validation Validate(string input)
{
    bool isValid = true; // todo: your validation
    return isValid ? Validation.Ok : Validation.Invalid("[todo: describe the validation]");
};

Expected behaviour

I should get:

[ValueObject<string>]
public readonly partial struct RedemptionId
{
    private static Validation Validate(string input)
    {
        bool isValid = true; // todo: your validation
        return isValid ? Validation.Ok : Validation.Invalid("[todo: describe the validation]");
    }
}