fix: incompatibility with djangocms-versioning-filer 1.3 was fixed (#1509)

When used with djangocms-versioning-filer, the `FileAdminChangeForm` might not
have a file field due to missing permissions.
Since djangocms-versioning-filer 1.3 the constructor of `FileAdminChangeForm`
crashes when opening the change URL of a published image.

This patch fixes this issue by adding a check whether the file field is present
before overriding it.

Signed-off-by: Florian Scherf <[email protected]>

Author: fscherf

filer/admin/fileadmin.py

@@ -35,7 +35,8 @@ class Meta:
 
     def __init__(self, *args, **kwargs):
         super().__init__(*args, **kwargs)
-        self.fields["file"].widget = forms.FileInput()
+        if "file" in self.fields:
+            self.fields["file"].widget = forms.FileInput()
 
     def clean(self):
         from ..validation import validate_upload