Make it possible to change/disable "change" link in group header/directory

[boonebgorges]

See https://wordpress.org/support/topic/option-to-switch-off-dialogue-on-group-profile/.

At a minimum, we can ensure that the 'change' element has proper selectors that allow it to be removed/modified using CSS or JS.

We could also add some sort of filter(s).

[r-a-y]

Button can be removed with the following snippet:

add_action( 'get_header', function() {
	if ( ! bp_is_groups_component() ) {
		return;
	}

	remove_action ( 'bp_group_header_meta', 'ass_group_subscribe_button' );
	remove_action ( 'bp_directory_groups_actions', 'ass_group_subscribe_button' );
} );