Description:
------------
The filter_var function, when used with FILTER_VALIDATE_EMAIL marks an email address with an = in it as invalid.

According to RFCs 822, 2822 and 5322, = is a valid component to the local-part of an e-mail address.

Reproduce code:
---------------
<?php    
    
$email_address = "test=mail@example.com";    
var_dump(filter_var($email_address, FILTER_VALIDATE_EMAIL));    
                                                                
$email_address = "test-mail@example.com";    
var_dump(filter_var($email_address, FILTER_VALIDATE_EMAIL));    
    
$email_address = "test+mail@example.com";    
var_dump(filter_var($email_address, FILTER_VALIDATE_EMAIL));    
                                                                        
?>


Expected result:
----------------
string(21) "test-mail@example.com"
string(21) "test-mail@example.com"
string(21) "test+mail@example.com"


Actual result:
--------------
bool(false)
string(21) "test+mail@example.com"
string(21) "test+mail@example.com"