[11.x] Simplify condition structure and add @throw to docblock for resolve method

[saMahmoudzadeh]

This PR updates the resolve method to exception handling by including RuntimeException in its throws clause within the doc block and simplifying the conditional structure.

We encounter the following code snippet in the resolve method:

if (! array_key_exists('driver', $config)) {
    throw new \RuntimeException("Instance [{$name}] does not specify a driver.");
}

Therefore, we can add the @throws RuntimeException to the doc block

Simplifying the conditional structure

if (isset($this->customCreators[$config['driver']])) {
    return $this->callCustomCreator($config);
} else {
    $driverMethod = 'create'.ucfirst($config['driver']).'Driver';

    if (method_exists($this, $driverMethod)) {
        return $this->{$driverMethod}($config);
    } else {
        throw new InvalidArgumentException("Instance driver [{$config['driver']}] is not supported.");
    }
}

In the above code, if the first if statement is executed, the else part will never be executed because a value is returned in this if, the same scenario happens in the else part as well. Therefore, we can simplify it a bit:

if (isset($this->customCreators[$config['driver']])) {
    return $this->callCustomCreator($config);
}

$driverMethod = 'create'.ucfirst($config['driver']).'Driver';

if (method_exists($this, $driverMethod)) {
    return $this->{$driverMethod}($config);
}

throw new InvalidArgumentException("Instance driver [{$config['driver']}] is not supported.");

[taylorotwell]

Thanks for your pull request to Laravel!

Unfortunately, I'm going to delay merging this code for now. To preserve our ability to adequately maintain the framework, we need to be very careful regarding the amount of code we include.

If possible, please consider releasing your code as a package so that the community can still take advantage of your contributions!

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