Move to Avalonia.Utilities

src/Avalonia.Base/Animation/SpringSolver.cs → src/Avalonia.Base/Utilities/SpringSolver.cs

@@ -24,9 +24,10 @@
  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
  * THE POSSIBILITY OF SUCH DAMAGE.
  */
+
 using System;
 
-namespace Avalonia.Animation;
+namespace Avalonia.Utilities;
 
 internal struct SpringSolver 
 {