Customizable clustergram line width

[hendraet]

Description

related to parts of #341
Adds a form element that lets users control the line width of the dendrograms that are part of a clustergram. Also updates the example workflow accordingly.

Testing

Create a run based on the "example dataset" workflow and run until clustergram step. Line width should be customizable in the form.

PR checklist

Development

• If necessary, I have updated the documentation (README, docstrings, etc.)
• If necessary, I have created / updated tests.

Mergeability

• main-branch has been merged into local branch to resolve conflicts
• The tests and linter have passed AFTER local merge
• The backend code has been formatted with black
• The frontend code has been formatted with pnpm format and checked with pnpm lint

Code review

• I have self-reviewed my code.
• At least one other developer reviewed and approved the changes

[github-actions]

Coverage report

This PR does not seem to contain any modification to coverable code.

[jorisfu]

LGTM, but change the current_step in the workflow before merging

[hendraet]

Noice, thx for the quick review