Copy a .strings file into the main iOS app bundle

I am working with a custom SDK that provides a localisation file to specify the labels used inside the SDK. The Localizable.strings file needs to be in the main bundle for it to be picked up by the SDK. Is there any way this can be done in an eas build. I am using a managed workflow and eas for building. I tried looking at creating a custom gymfile to copy the file but didnt find any option to do it. One way it was possible is by writing a ruby script and tag it as an action in the fastfile but I am not sure where the fastfile is created and how to customize it. Any help would be greatly appreciated.