When creating an action_menu, we can use set_kebab_trigger() to set the action menu button as a kebab icon with the following classes "btn btn-icon d-flex align-items-center justify-content-center no-caret" (defined in const DEFAULT_KEBAB_TRIGGER_CLASSES).

For the course activity cards, the action menu buttons were re-styled, showing them a bit smaller and instead of circular, just rounded (Used in each activity card actions button and group mode selector).
And for the sections, the action menu button is the same, but a bit bigger.

We should unify the styles (rounded vs circular) of the action menu, and add proper ways to define the sizes instead of overriding the styles in different SCSS files.