[5.3] Fix an issue with sometimes when it comes to wildcard rules

[themsaid]

$data = [
    "cities" => [
        [
            "name" => ["NY"]
        ]
    ]
];

$validator = Validator::make($data, [
    "cities.*.name" => "sometimes|required|string",
]);

Currently the validation will pas even though the name is an array instead of a string, that's because cities.0.name doesn't exist when sometimes checks for it in passesOptionalCheck().

This PR fixes that by appending wildcard keys to the $data array before the check.

[vigneshgurusamy]

@themsaid $data is needed only when the attribute has sometimes rule. Could you move data extraction logic inside if condition?