This commit adds bottom margin to label elements of
different inputs by adding "modal-field-label" class
to the label elements. Some of them already have the
margin due to having dropdown-title class.
Adds an option to the generate bot URL modal to filter for events
that will trigger notifications. This option is conditionally
displayed when only `all_event_types` is defined for the selected
integration.
If selected, the URL will display all events by default. There
are "check all" and "uncheck all" buttons to easily include or
remove all the events from the URL.
Fixes#27628.