chore: add GUT test framework

addons/gut/test/panel_demo_scripts/test_all_passing.gd

@@ -0,0 +1,42 @@
+extends 'res://addons/gut/test.gd'
+
+
+func test_passing_1():
+	pass_test("this passes")
+
+func test_passing_2():
+	pass_test("this passes")
+
+func test_passing_3():
+	pass_test("this passes")
+
+func test_passing_4():
+	pass_test("this passes")
+
+func test_passing_5():
+	pass_test("this passes")
+
+func test_passing_6():
+	pass_test("this passes")
+
+func test_passing_7():
+	pass_test("this passes")
+
+func test_passing_8():
+	pass_test("this passes")
+
+func test_passing_9():
+	pass_test("this passes")
+
+func test_passing_10():
+	pass_test("this passes")
+
+func test_passing_11():
+	pass_test("this passes")
+
+func test_passing_12():
+	pass_test("this passes")
+
+func test_passing_13():
+	pass_test("this passes")
+