Update textureregion.cs (#153)

Fix the comments for the constructor

Author: jani-r

articles/tutorials/building_2d_games/07_optimizing_texture_rendering/snippets/textureregion.cs

@@ -46,7 +46,7 @@ public TextureRegion() { }
     /// </summary>
     /// <param name="texture">The texture to use as the source texture for this texture region.</param>
     /// <param name="x">The x-coordinate position of the upper-left corner of this texture region relative to the upper-left corner of the source texture.</param>
-    /// <param name="y"><The y-coordinate position of the upper-left corner of this texture region relative to the upper-left corner of the source texture./param>
+    /// <param name="y">The y-coordinate position of the upper-left corner of this texture region relative to the upper-left corner of the source texture.</param>
     /// <param name="width">The width, in pixels, of this texture region.</param>
     /// <param name="height">The height, in pixels, of this texture region.</param>
     public TextureRegion(Texture2D texture, int x, int y, int width, int height)