[libadwaita/wip/exalm/animation-docs] animation: Mention AdwSpringAnimation in docs

[Alexander Mikhaylenko <alexm src gnome org>]

commit 4132507c559afb643ccdc29d4e703ddeb20413e1
Author: Alexander Mikhaylenko <alexm gnome org>
Date:   Mon Dec 6 23:16:26 2021 +0500

    animation: Mention AdwSpringAnimation in docs

 src/adw-animation.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)
---
diff --git a/src/adw-animation.c b/src/adw-animation.c
index bb46fc37..818bf240 100644
--- a/src/adw-animation.c
+++ b/src/adw-animation.c
@@ -21,8 +21,8 @@
  * provides a value to animate, and a state indicating whether the
  * animation hasn't been started yet, is playing, paused or finished.
  *
- * Currently there's only one concrete animation type:
- * [class@Adw.TimedAnimation].
+ * Currently there are two concrete animation types:
+ * [class@Adw.TimedAnimation] and [class@Adw.SpringAnimation].
  *
  * `AdwAnimation` will automatically skip the animation if
  * [property@Adw.Animation:widget] is unmapped, or if