Find method by SOAP action

[veewee]

Q	A
Type	feature
BC Break	no
Fixed issues

Summary

Provides a way to find a method based on SoapAction:

// The soap action can be detected from a PSR-7 request headers by using:
// https://github.com/php-soap/psr18-transport/blob/main/src/HttpBinding/SoapActionDetector.php
$soapAction = 'http://tempuri.org/Add';

$method = $metadata->getMethods()->fetchBySoapAction($soapAction),

This comes in handy for soap servers : php-soap/encoding#32