Remove duplicate class eZPendingActions

The class is already defined in kernel/classes/ezpendingactions.php and causes a warning when generating autoloads:

```
Warning:
Class eZPendingActions in file extension/sqliimport/classes/ezpendingactions.php is already defined in:
kernel/classes/ezpendingactions.php (autoload/ezp_kernel.php)
This class was not added to the autoload array.
```

which is disarmed later, when the kernel overrides are created:

````
Class eZPendingActions in file extension/sqliimport/classes/ezpendingactions.php will override:
kernel/classes/ezpendingactions.php (autoload/ezp_kernel.php)
```

but nonetheless...

Cheers
:octocat: Jérôme

PS: Great extension, Jérôme! :)