GDScript: Fix incorrect setter call for reference types

modules/gdscript/tests/scripts/runtime/features/setter_chain_shared_types.gd

@@ -0,0 +1,62 @@
+# GH-94667
+
+class Inner:
+	var subprop: Vector2:
+		set(value):
+			prints("subprop setter", value)
+			subprop = value
+		get:
+			print("subprop getter")
+			return subprop
+
+	func _to_string() -> String:
+		return "<Inner>"
+
+var prop1:
+	set(value):
+		prints("prop1 setter", value)
+		prop1 = value
+
+var prop2: Inner:
+	set(value):
+		prints("prop2 setter", value)
+		prop2 = value
+
+var prop3:
+	set(value):
+		prints("prop3 setter", value)
+		prop3 = value
+	get:
+		print("prop3 getter")
+		return prop3
+
+var prop4: Inner:
+	set(value):
+		prints("prop4 setter", value)
+		prop4 = value
+	get:
+		print("prop4 getter")
+		return prop4
+
+func test():
+	print("===")
+	prop1 = Vector2()
+	prop1.x = 1.0
+	print("---")
+	prop1 = Inner.new()
+	prop1.subprop.x = 1.0
+
+	print("===")
+	prop2 = Inner.new()
+	prop2.subprop.x = 1.0
+
+	print("===")
+	prop3 = Vector2()
+	prop3.x = 1.0
+	print("---")
+	prop3 = Inner.new()
+	prop3.subprop.x = 1.0
+
+	print("===")
+	prop4 = Inner.new()
+	prop4.subprop.x = 1.0

modules/gdscript/tests/scripts/runtime/features/setter_chain_shared_types.out

@@ -0,0 +1,26 @@
+GDTEST_OK
+===
+prop1 setter (0, 0)
+prop1 setter (1, 0)
+---
+prop1 setter <Inner>
+subprop getter
+subprop setter (1, 0)
+===
+prop2 setter <Inner>
+subprop getter
+subprop setter (1, 0)
+===
+prop3 setter (0, 0)
+prop3 getter
+prop3 setter (1, 0)
+---
+prop3 setter <Inner>
+prop3 getter
+subprop getter
+subprop setter (1, 0)
+===
+prop4 setter <Inner>
+prop4 getter
+subprop getter
+subprop setter (1, 0)