Compatibility with PHP8.1

Please review.

I check with #4 and it fixed the issue.

@apatel0325 the issue cannot be marked as fixed directly. You need to mark it as RTBC with proper screenshots and testing steps.
The project maintainer will change the status to fixed after committing the fix to the codebase.

You can check the different issue status here:
https://www.drupal.org/docs/develop/issues/fields-and-other-parts-of-an-... →

Reviewed the MR and tested the patch locally.
The patch applies cleanly and the deprecation errors are removed.

Checking patch electra.theme...
Applied patch electra.theme cleanly.

@arisen Thank you for letting me know.