message: chore(Root): set forwards fill mode for back animations
diff: }
  .Root--ios .Root__view--show-back::after {
  - animation: vkui-root-ios-animation-show-back 0.6s var(--ios-easing);
  + animation: vkui-root-ios-animation-show-back 0.6s var(--ios-easing) forwards;
  }
  .Root--ios .Root__view--hide-forward::after {
  }
  .Root--ios .Root__view--hide-back {
  - animation: vkui-root-ios-animation-hide-back 0.6s var(--ios-easing);
  + animation: vkui-root-ios-animation-hide-back 0.6s var(--ios-easing) forwards;
  }
  @keyframes vkui-root-ios-animation-show-back {
  .Root--android .Root__view--hide-back,
  .Root--vkcom .Root__view--hide-back {
  - animation: vkui-root-android-animation-hide-back 0.3s var(--android-easing);
  + animation: vkui-root-android-animation-hide-back 0.3s var(--android-easing)
  + forwards;
  }
  @keyframes vkui-root-android-animation-hide-back {
  