Added text and divider component

[maxchristlmck]

Description

Add a text and a divider component to controls. This allows the user to add text and dividers to the sidebar.

Screenshot

Checklist

• I have not referenced individuals, products or companies in any commits, directly or indirectly
• I have not added data or restricted code in any commits, directly or indirectly
• I have updated the docstring of any public function/class/model changed
• I have added the PR number to the change description in the changelog fragment, e.g. Enable feature XXX ([#1](https://github.com/mckinsey/vizro/pull/1)) (if applicable)
• I have added tests to cover my changes (if applicable)

Types of changes

• Docs/refactoring (non-breaking change which improves codebase)
• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)

Notice

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  • I certify that the use of this contribution as authorised by the Apache 2.0 license does not violate the intellectual property rights of anyone else.

[huong-li-nguyen]

Hey @maxchristlmck ,

thanks for raising the PR! I am sure this visual element can be helpful for many :)

I just looked through your changes and I have an idea of how this can be achieved without creating two new models. I think all of this can be achieved via the existing Card model and its existing markdown component. In general Markdown is really flexible, so you can create horizontal rulers via markdown as well.

Let me raise an Issue and we can discuss there :) See: #82