Resolve "Convert Insights to ECharts"

What does this MR do?

This MR moves the existing chart components over to the GitLab UI chart components: GlColumnChart, GlStackedColumnChart and GlLineChart.

We don't have a corresponding pie chart so this has been removed. Any reference to these now will fall back to bar charts instead. There is great discussion about the usefulness of pie charts which shows how other graph types are better suited.

There are two other issues to resolve in future:

1. Moving the tests from karma to jest
2. Update the documentation screenshots

Screenshots

Does this MR meet the acceptance criteria?

Conformity

• Changelog entry
• Documentation (if required)
• Code review guidelines
• Merge request performance guidelines
• Style guides
• Database guides
• Separation of EE specific content

Availability and Testing

Test that /%GROUP_NAME%/%PROJECT_NAME%/insights#/issues and /groups/%GROUP_NAME%/-/insights#/issues show the charts correctly. You may need to update the configuration YML file as described in https://docs.gitlab.com/ee/user/project/insights/#writing-your-gitlabinsightsyml

• Review and add/update tests for this feature/bug. Consider all test levels. See the Test Planning Process.
• Tested in all supported browsers
• Informed Infrastructure department of a default or new setting change, if applicable per definition of done

Security

If this MR contains changes to processing or storing of credentials or tokens, authorization and authentication methods and other items described in the security review guidelines:

• Label as security and @ mention @gitlab-com/gl-security/appsec
• The MR includes necessary changes to maintain consistency between UI, API, email, or other methods
• Security reports checked/validated by a reviewer from the AppSec team

Closes #196184 (closed), #13006 (closed)