Bump dependencies. Some parts needed to be deactivated for that. They need to be reimplemented.

- breadcrumbs (!flask-breadcrumbs)
- manual modal button
- api blueprint (!flask-marshmallow/!marshmallow-sqlalchemy)

app/workshops/routes.py

@@ -1,16 +1,13 @@
 from flask import redirect, render_template, url_for
-from flask_breadcrumbs import register_breadcrumb
 from . import bp
 
 
 @bp.route('')
-@register_breadcrumb(bp, '.', '<i class="material-icons left">business_center</i>Workshops')
 def workshops():
     return redirect(url_for('main.dashboard'))
 
 
 @bp.route('/fgho_sommerschule_2023')
-@register_breadcrumb(bp, '.fgho_sommerschule_2023', 'FGHO Sommerschule 2023')
 def fgho_sommerschule_2023():
     return render_template(
         'workshops/fgho_sommerschule_2023.html.j2',