[.NET] Use collection expressions in docs

As of C# 12 we can now use collection expressions to reduce some boilerplate when initializing collections.

doc/classes/Array.xml

@@ -17,14 +17,14 @@
 		print(array[-3]) # Prints "Second"
 		[/gdscript]
 		[csharp]
-		var array = new Godot.Collections.Array{"First", 2, 3, "Last"};
+		Godot.Collections.Array array = ["First", 2, 3, "Last"];
 		GD.Print(array[0]); // Prints "First"
 		GD.Print(array[2]); // Prints 3
-		GD.Print(array[array.Count - 1]); // Prints "Last"
+		GD.Print(array[^1]); // Prints "Last"
 
-		array[2] = "Second";
+		array[1] = "Second";
 		GD.Print(array[1]); // Prints "Second"
-		GD.Print(array[array.Count - 3]); // Prints "Second"
+		GD.Print(array[^3]); // Prints "Second"
 		[/csharp]
 		[/codeblocks]
 		[b]Note:[/b] Arrays are always passed by [b]reference[/b]. To get a copy of an array that can be modified independently of the original array, use [method duplicate].
@@ -358,7 +358,7 @@
 				print(array) # Prints [2, 2, 2, 2, 2]
 				[/gdscript]
 				[csharp]
-				var array = new Godot.Collections.Array();
+				Godot.Collections.Array array = [];
 				array.Resize(5);
 				array.Fill(2);
 				GD.Print(array); // Prints [2, 2, 2, 2, 2]
@@ -460,7 +460,7 @@
 				print(["inside", 7].has("7"))       # Prints false
 				[/gdscript]
 				[csharp]
-				var arr = new Godot.Collections.Array { "inside", 7 };
+				Godot.Collections.Array arr = ["inside", 7];
 				// By C# convention, this method is renamed to `Contains`.
 				GD.Print(arr.Contains("inside"));  // Prints True
 				GD.Print(arr.Contains("outside")); // Prints False
@@ -573,7 +573,7 @@
 				print([1, 2, 3.25, "Hi"].pick_random())
 				[/gdscript]
 				[csharp]
-				var array = new Godot.Collections.Array { 1, 2, 3.25f, "Hi" };
+				Godot.Collections.Array array = [1, 2, 3.25f, "Hi"];
 				GD.Print(array.PickRandom()); // May print 1, 2, 3.25, or "Hi".
 				[/csharp]
 				[/codeblocks]
@@ -755,7 +755,7 @@
 				print(numbers) # Prints [2.5, 5, 8, 10]
 				[/gdscript]
 				[csharp]
-				var numbers = new Godot.Collections.Array { 10, 5, 2.5, 8 };
+				Godot.Collections.Array numbers = [10, 5, 2.5, 8];
 				numbers.Sort();
 				GD.Print(numbers); // Prints [2.5, 5, 8, 10]
 				[/csharp]
@@ -817,8 +817,8 @@
 				[/gdscript]
 				[csharp]
 				// Note that concatenation is not possible with C#'s native Array type.
-				var array1 = new Godot.Collections.Array{"One", 2};
-				var array2 = new Godot.Collections.Array{3, "Four"};
+				Godot.Collections.Array array1 = ["One", 2];
+				Godot.Collections.Array array2 = [3, "Four"];
 				GD.Print(array1 + array2); // Prints ["One", 2, 3, "Four"]
 				[/csharp]
 				[/codeblocks]