Don't open instant results modal if an autosuggest suggestion is selected.

[JakePT]

…cted.

Description of the Change

Prevents the Instant Results modal from opening if an Autosuggest suggestion is highlighted, allowing the user to open the suggestion with the Enter key without a conflict.

Closes #3824

How to test the Change

1. Activate Instant Results and Autosuggest.
2. Enter a search query so that suggestions appear.
3. Navigate to a suggestion with the arrow keys and press Enter.
4. You should be taken to the suggestion and Instant Results should not launch,

Changelog Entry

Fixed - An issue where pressing Enter to select an Autosuggest suggestion would instead open Instant Results.

Credits

Props @JakePT

Checklist:

• [x] I agree to follow this project's Code of Conduct.
• [ ] I have updated the documentation accordingly.
• [x] I have added tests to cover my change.
• [x] All new and existing tests pass.