Failing API requests will never time out

I’ve discovered that when the plugin is not able to connect to Spotler mail+ (for any reason, for example the api is down, firewall blocking the request, etc), and a request never finishes, a timeout is never triggered. Instead, it will try to load forever. This can make some pages unresponsive.

This is caused by the API client that gets created, which isn’t passed a timeout parameter. This will then use the default of the guzzle client, which is 0 (indefinitely).

I would like to propose to add a default timeout value when creating a client, as well as adding a wordpress filter so theme developers can modify the behavior.

The old code:

$this->client = new Client( [
	'base_uri' => self::SPOTLER_DEFAULT_API_URL,
	'handler'  => $stack,
	'auth'     => 'oauth',
] );

The new code (with a timeout of for example 10 seconds):

$client_config = [
	'base_uri' => self::SPOTLER_DEFAULT_API_URL,
	'handler'  => $stack,
	'auth'     => 'oauth',
	'timeout'  => 10,
];
$client_config = apply_filters( 'mailplus_forms_client_config', $client_config );
$this->client  = new Client( $client_config );