Added support for access token of string type

[serious-angel]

Dear Developers, Artsts,

Thank you for the marvel you do...

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Are we sure it is the valid access to the variable of access token?:

Providers/src/VKID/Provider.php

Line 59 in 4789031

'access_token' => $token['access_token'],

Considering that the $token already is a string obtained from the following vendor method?:

protected function parseAccessToken($body)
{
    return Arr::get($body, 'access_token');
}

Source

Wouldn't we get an exception in that case?:

// Socialite::with('vkid')->user();
Cannot access offset of type string on string

We may see a similar approach in the following provider:

Providers/src/VKontakte/Provider.php

Lines 42 to 46 in 4789031

	if (is_array($token)) {
	$formToken['email'] = $token['email'] ?? null;
	$token = $token['access_token'];
	}

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Best and kind regards ✨