Add return type declaration to implement ArrayAccess interface in PHP 8.1

[arwin009]

https://github.com/webapix/mygls-sdk/blob/abc87c34ac3415e0bcf7c02228fb9349268bdf0b/src/Responses/Response.php#L51 https://github.com/webapix/mygls-sdk/blob/abc87c34ac3415e0bcf7c02228fb9349268bdf0b/src/Responses/Response.php#L62 https://github.com/webapix/mygls-sdk/blob/abc87c34ac3415e0bcf7c02228fb9349268bdf0b/src/Responses/Response.php#L76 https://github.com/webapix/mygls-sdk/blob/abc87c34ac3415e0bcf7c02228fb9349268bdf0b/src/Responses/Response.php#L89

These methods should have return types declared to be compatible with PHP 8.1:

interface ArrayAccess {
    /* Methods */
    public offsetExists(mixed $offset): bool
    public offsetGet(mixed $offset): mixed
    public offsetSet(mixed $offset, mixed $value): void
    public offsetUnset(mixed $offset): void
}

[zsocakave]

New version released, 2.x now PHP8.1 compatible.

[arwin009]

Thank you!