Issue #3449577 by dydave: GitlabCI: Fixed all ESLINT validation errors.

https://www.drupal.org/project/admin_toolbar/issues/3449577

✅ ESLint: Fixed all errors reported on GitlabCI:

• Fixed all validation errors such as unnamed functions, variable names, indentations, etc...
• Added file .eslintignore to exclude external hoverIntent jQuery Plugin library from validation.
• Ignored certain lines of code which would need to be refactored to vanilla JS (jquery/no- rules).

Based on MR !75 (closed)