GDScript: Fix UNSAFE_CAST warning

modules/gdscript/tests/scripts/runtime/errors/cast_freed_object.gd

@@ -0,0 +1,4 @@
+func test():
+	var node := Node.new()
+	node.free()
+	print(node as Node2D)

modules/gdscript/tests/scripts/runtime/errors/cast_freed_object.out

@@ -0,0 +1,6 @@
+GDTEST_RUNTIME_ERROR
+>> SCRIPT ERROR
+>> on function: test()
+>> runtime/errors/cast_freed_object.gd
+>> 4
+>> Trying to cast a freed object.

modules/gdscript/tests/scripts/runtime/errors/cast_int_to_array.gd

@@ -0,0 +1,4 @@
+func test():
+	var integer: Variant = 1
+	@warning_ignore("unsafe_cast")
+	print(integer as Array)

modules/gdscript/tests/scripts/runtime/errors/cast_int_to_array.out

@@ -0,0 +1,6 @@
+GDTEST_RUNTIME_ERROR
+>> SCRIPT ERROR
+>> on function: test()
+>> runtime/errors/cast_int_to_array.gd
+>> 4
+>> Invalid cast: could not convert value to 'Array'.

modules/gdscript/tests/scripts/runtime/errors/cast_int_to_object.gd

@@ -0,0 +1,4 @@
+func test():
+	var integer: Variant = 1
+	@warning_ignore("unsafe_cast")
+	print(integer as Node)

modules/gdscript/tests/scripts/runtime/errors/cast_int_to_object.out

@@ -0,0 +1,6 @@
+GDTEST_RUNTIME_ERROR
+>> SCRIPT ERROR
+>> on function: test()
+>> runtime/errors/cast_int_to_object.gd
+>> 4
+>> Invalid cast: can't convert a non-object value to an object type.

modules/gdscript/tests/scripts/runtime/errors/cast_object_to_int.gd

@@ -0,0 +1,4 @@
+func test():
+	var object: Variant = RefCounted.new()
+	@warning_ignore("unsafe_cast")
+	print(object as int)

modules/gdscript/tests/scripts/runtime/errors/cast_object_to_int.out

@@ -0,0 +1,6 @@
+GDTEST_RUNTIME_ERROR
+>> SCRIPT ERROR
+>> on function: test()
+>> runtime/errors/cast_object_to_int.gd
+>> 4
+>> Invalid cast: could not convert value to 'int'.