Fix XML in Plane.cs

modules/mono/glue/GodotSharp/GodotSharp/Core/Plane.cs

@@ -22,7 +22,7 @@ namespace Godot
         /// <summary>
         /// The normal of the plane, which must be normalized.
         /// In the scalar equation of the plane `ax + by + cz = d`, this is
-        /// the vector `(a, b, c)`, where `d` is the <see cref="D"> property.
+        /// the vector `(a, b, c)`, where `d` is the <see cref="D"/> property.
         /// </summary>
         /// <value>Equivalent to `x`, `y`, and `z`.</value>
         public Vector3 Normal
@@ -84,7 +84,7 @@ namespace Godot
         /// <see cref="Normal"/>). This value is typically non-negative.
         /// In the scalar equation of the plane `ax + by + cz = d`,
         /// this is `d`, while the `(a, b, c)` coordinates are represented
-        /// by the <see cref="Normal"> property.
+        /// by the <see cref="Normal"/> property.
         /// </summary>
         /// <value>The plane's distance from the origin.</value>
         public real_t D { get; set; }