added react-router-dom navlinks component

[alucernoni]

For an example of how to fill this template out, see this Pull Request.

Description

Replaced tags with react-router-dom NavLink component and routed links to matching router paths

Related Issue

closes #2

Acceptance Criteria

1. The nav element is added to the Layout component
2. Links to the "Home", "List", and "Add item" pages of the app are In the nav element
3. The links all function as expected using the NavLink component from react-router-dom

Type of Changes

	Type
✓	🐛 Bug fix
	✨ New feature
	🔨 Refactoring
	💯 Add tests
	🔗 Update dependencies
	📜 Docs

Updates

Before

After

Testing Steps / QA Criteria

[github-actions]

Visit the preview URL for this PR (updated for commit bcfc390):

https://tcl-56-smart-shopping-li-ffe7d--pr16-dn-al-navlinks-0db6pmvv.web.app

_{(expires Mon, 10 Apr 2023 23:07:49 GMT)}

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_{Sign: 9c51cec5927ae3f1253a2134be95c1a07393f9a7}

[yiremorlans]

simple and readable code -- great!

[ashleyvalentine]

Looks great!

[adidalal]

Not a blocker or necessarily in scope for this week, and we can discover this together - consider how we could test this?