Invalid array for `$sources` in `filter_srcset_attr` hook

[Soare-Robert-Daniel]

Description

The warning reported by the user:

[ PHP Warning: foreach() argument must be of type array|object, bool given in /nas/content/live/intgrtdsrlife/wp-content/plugins/optimole-wp/inc/tag_replacer.php on line 835]

The array check for $sources in filter_srcset_attr was removed in 407e4fe on the premise that the good data is always served correctly.

Step-by-step reproduction instructions

1. Add a custom filter for the WP hook 'wp_calculate_image_srcset' that returns a non-array value.
2. Check the logs for warnings

Screenshots, screen recording, code snippet or Help Scout ticket

Help Scout ticket: https://secure.helpscout.net/conversation/3136637806/476060?viewId=2353196

Environment info

No response

Is the issue you are reporting a regression

Yes, this is a regression.