Fix console error when left-nav accordion is empty

[akasjain2]

When there are no elements in accordion-ml, then a console error appears

failed to load module for accordion-ml TypeError: Cannot read properties of null (reading 'parentElement')
at Module.decorate (accordion-ml.js:241:31)
at aem.js:581:32

[mreyescc]

Team will look into recreating this error to see if this still exists as an issue.

[jluicc]

This issue seems to happen when there is an empty "Accordion-ml" block inside of a word document.

Here is what the word document looks like when reproducing the error: