Fix incorrect logic

The following commit 64ae94b introduced an inversion of the logic for this condition:
```
!empty($interfaceMappings)
```
became:
```
!$interfaceMappings
```

The result means that the ```ResolveTargetEntityListener``` doctrine.xml config is never generated when interfaces are used.

Author: Gary Lockett

src/TypesGenerator.php

@@ -438,7 +438,7 @@ public function generate(array $config): void
             }
         }
 
-        if (!$interfaceMappings && $config['doctrine']['resolveTargetEntityConfigPath']) {
+        if (count($interfaceMappings) > 0 && $config['doctrine']['resolveTargetEntityConfigPath']) {
             $file = $config['output'].'/'.$config['doctrine']['resolveTargetEntityConfigPath'];
             $dir = \dirname($file);
             if (!file_exists($dir)) {