chore: remove repetitive words (#15427)

Signed-off-by: careworry <worrycare@outlook.com>
Co-authored-by: Max Katz <maxkatz6@outlook.com>

src/Avalonia.Base/AvaloniaProperty.cs

@@ -151,7 +151,7 @@ namespace Avalonia
         /// </summary>
         /// <remarks>
         /// When a property changes, change notifications are sent to all property subscribers;
-        /// for example via the <see cref="AvaloniaProperty.Changed"/> observable and and the
+        /// for example via the <see cref="AvaloniaProperty.Changed"/> observable and the
         /// <see cref="AvaloniaObject.PropertyChanged"/> event. If this callback is set for a property,
         /// then it will be called before and after these notifications take place. The bool argument
         /// will be true before the property change notifications are sent and false afterwards. This

src/Avalonia.Base/Layout/Layoutable.cs

@@ -791,7 +791,7 @@ namespace Avalonia.Layout
                     InvalidateMeasure();
 
                     // If any descendant had its measure/arrange invalidated while we were hidden,
-                    // they will need to to be registered with the layout manager now that they
+                    // they will need to be registered with the layout manager now that they
                     // are again effectively visible. If IsEffectivelyVisible becomes an observable
                     // property then we can piggy-pack on that; for the moment we do this manually.
                     if (VisualRoot is ILayoutRoot layoutRoot)

src/Avalonia.Base/Media/TextFormatting/Unicode/BiDiAlgorithm.cs

@@ -1580,7 +1580,7 @@ namespace Avalonia.Media.TextFormatting.Unicode
         }
 
         /// <summary>
-        /// Check if a a directionality is neutral for rules N1 and N2
+        /// Check if a directionality is neutral for rules N1 and N2
         /// </summary>
         [MethodImpl(MethodImplOptions.AggressiveInlining)]
         private static bool IsNeutralClass(BidiClass direction)

src/Avalonia.Base/PixelRect.cs

@@ -150,7 +150,7 @@ namespace Avalonia
         }
 
         /// <summary>
-        /// Determines whether a point in in the bounds of the rectangle.
+        /// Determines whether a point in the bounds of the rectangle.
         /// </summary>
         /// <param name="p">The point.</param>
         /// <returns>true if the point is in the bounds of the rectangle; otherwise false.</returns>

src/Avalonia.Base/Utilities/BinarySearchExtension.cs

@@ -44,7 +44,7 @@ namespace Avalonia.Utilities
         }
 
         /// <summary>
-        /// Performs a binary search on a a subset of an IReadOnlyList
+        /// Performs a binary search on a subset of an IReadOnlyList
         /// </summary>
         /// <typeparam name="T">The list element type</typeparam>
         /// <param name="list">The list to be searched</param>

src/Avalonia.Base/Utilities/SpringSolver.cs

@@ -84,7 +84,7 @@ internal struct SpringSolver
     /// <summary>
     /// 
     /// </summary>
-    /// <param name="ωn">The the natural frequency of the system [rad/s].</param>
+    /// <param name="ωn">The natural frequency of the system [rad/s].</param>
     /// <param name="zeta">The damping ratio.</param>
     /// <param name="initialVelocity"></param>
     public SpringSolver(double ωn, double zeta, double initialVelocity)

src/Avalonia.Controls/NativeControlHost.cs

@@ -88,7 +88,7 @@ namespace Avalonia.Controls
                 }
 
                 // If there is no attachment, but the control exists,
-                // attempt to attach to to the current toplevel or destroy the control if it's incompatible
+                // attempt to attach to the current toplevel or destroy the control if it's incompatible
                 if (_attachment == null && _nativeControlHandle != null)
                 {
                     if (_currentHost.IsCompatibleWith(_nativeControlHandle))

src/Avalonia.Controls/Platform/IPlatformLifetimeEventsImpl.cs

@@ -11,7 +11,7 @@ namespace Avalonia.Platform
         /// Raised by the platform when a shutdown is requested.
         /// </summary>
         /// <remarks>
-        /// Raised on on OSX via the Quit menu or right-clicking on the application icon and selecting Quit.
+        /// Raised on OSX via the Quit menu or right-clicking on the application icon and selecting Quit.
         /// </remarks>
         event EventHandler<ShutdownRequestedEventArgs>? ShutdownRequested;
     }

src/Avalonia.Controls/Primitives/PopupPositioning/IPopupPositioner.cs

@@ -56,7 +56,7 @@ namespace Avalonia.Controls.Primitives.PopupPositioning
     /// Provides positioning parameters to <see cref="IPopupPositioner"/>.
     /// </summary>
     /// <remarks>
-    /// The IPopupPositioner provides a collection of rules for the placement of a a popup relative
+    /// The IPopupPositioner provides a collection of rules for the placement of a popup relative
     /// to its parent. Rules can be defined to ensure the popup remains within the visible area's
     /// borders, and to specify how the popup changes its position, such as sliding along an axis,
     /// or flipping around a rectangle. These positioner-created rules are constrained by the