message: Introduce lifetime to `on_change` handler for `Toggler`
diff: @@ -33,7 +33,7 @@ pub use iced_style::toggler::{Style, StyleSheet};
  #[allow(missing_debug_implementations)]
  pub struct Toggler<'a, Message, Renderer: text::Renderer> {
  is_active: bool,
  - on_toggle: Box<dyn Fn(bool) -> Message>,
  + on_toggle: Box<dyn Fn(bool) -> Message + 'a>,
  label: Option<String>,
  width: Length,
  size: u16,
  @@ -62,7 +62,7 @@ impl<'a, Message, Renderer: text::Renderer> Toggler<'a, Message, Renderer> {
  f: F,
  ) -> Self
  where
  - F: 'static + Fn(bool) -> Message,
  + F: 'a + Fn(bool) -> Message,
  {
  Toggler {
  is_active,
  