Add link to Symfony UX Chart.js and add description for Wicked Charts

[srich387]

Awesome Contribution Checklist:

• [x] I have read, and re-read the Contributing Guidelines
• [x] I have searched to ensure the suggested item doesn't exist on this list
• [x] This PR contains only one item

Please Describe Your Addition

• Added link to Symfony UX Chart.js bundle
• Added description for Wicked Charts

There is a previous PR regarding the Symfony UX bundle, #49, which was closed due to inactivity. For evidence that the Symfony UX bundle supports only Chart.js v3, see the bundle's package.json file.