[#62] Fixed closing of the descendant item with a keyboard collapsing ancestor items in Side Navigation component.

[joshua-salsadigital]

Closes #62

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Changed

1. Fixed Collapsible acts differently on spacebar and enter keys.

Screenshots

[github-actions]

🚀 Deployed on https://65f2e8b275b329c3c6b183ae--civictheme-uikit.netlify.app

[joshua-salsadigital]

Test PR: https://nginx-php.pr-1232.civictheme-monorepo-drupal.lagoon.salsa.hosting/

[AlexSkrypnyk]

@joshua-salsadigital
This fix is so elegant! 💅