fix(accordion): toggle icon now shows up in vue and react

[liamdebeasi]

Pull request checklist

Please check if your PR fulfills the following requirements:

• Tests for the changes have been added (for bug fixes / features)
• Docs have been reviewed and added / updated if needed (for bug fixes / features)
• Build (npm run build) was run locally and any changes were pushed
• Lint (npm run lint) has passed locally and any fixes were made for failures

Pull request type

Please check the type of change your PR introduces:

• Bugfix
• Feature
• Code style update (formatting, renaming)
• Refactoring (no functional changes, no api changes)
• Build related changes
• Documentation content changes
• Other (please describe):

What is the current behavior?

Vue and React use imports for icons, and since chevronDown was not explicitly imported, the icon never showed up when using accordion in these apps

What is the new behavior?

• Added explicit import for chevronDown in react and vue

Does this introduce a breaking change?

• Yes
• No

Other information