Updated chart.js dependency to 2.9.4 to resolve HIGH vulnerability P…

[ghost]

…rototype pollution in chart.js

Prototype pollution in chart.js vulnerability issue is resolved in v2.9.4 of chart.js

Description of change

Pull Request check-list

• Run gulp test to ensure there are no linting, or style issues and all tests pass.
• Squash your commits into a few commits only.
• Make sure the commit message is short, concise and descriptive of the issues you're fixing.
• Avoid mixing up multiple issues and/or features, open one pull request for each issue.
• [] Have you updated the documentation and / or examples?
• [] Have you included a new test?

[jtblin]

This PR was automatically closed following the migration to the main branch and the deletion of the master branch.

Since the project is now officially on Chart.js v2.9.4 in the main branch, this enhancement is already implemented. Thank you!