Fix GDScript base and outer classes, signals and functions lookup order

- Add outer class lookup test
- Add signal lookup test

Co-authored-by: Dmitrii Maganov <vonagam@gmail.com>

modules/gdscript/tests/scripts/analyzer/errors/outer_class_constants.gd

@@ -0,0 +1,8 @@
+class Outer:
+	const OUTER_CONST: = 0
+	class Inner:
+		pass
+
+func test() -> void:
+	var type: = Outer.Inner
+	print(type.OUTER_CONST)

modules/gdscript/tests/scripts/analyzer/errors/outer_class_constants.out

@@ -0,0 +1,6 @@
+GDTEST_RUNTIME_ERROR
+>> SCRIPT ERROR
+>> on function: test()
+>> analyzer/errors/outer_class_constants.gd
+>> 8
+>> Invalid get index 'OUTER_CONST' (on base: 'GDScript').

modules/gdscript/tests/scripts/analyzer/errors/outer_class_constants_as_variant.gd

@@ -0,0 +1,9 @@
+class Outer:
+	const OUTER_CONST: = 0
+	class Inner:
+		pass
+
+func test() -> void:
+	var type: = Outer.Inner
+	var type_v: Variant = type
+	print(type_v.OUTER_CONST)

modules/gdscript/tests/scripts/analyzer/errors/outer_class_constants_as_variant.out

@@ -0,0 +1,6 @@
+GDTEST_RUNTIME_ERROR
+>> SCRIPT ERROR
+>> on function: test()
+>> analyzer/errors/outer_class_constants_as_variant.gd
+>> 9
+>> Invalid get index 'OUTER_CONST' (on base: 'GDScript').

modules/gdscript/tests/scripts/analyzer/errors/outer_class_instance_constants.gd

@@ -0,0 +1,8 @@
+class Outer:
+	const OUTER_CONST: = 0
+	class Inner:
+		pass
+
+func test() -> void:
+	var instance: = Outer.Inner.new()
+	print(instance.OUTER_CONST)

modules/gdscript/tests/scripts/analyzer/errors/outer_class_instance_constants.out

@@ -0,0 +1,6 @@
+GDTEST_RUNTIME_ERROR
+>> SCRIPT ERROR
+>> on function: test()
+>> analyzer/errors/outer_class_instance_constants.gd
+>> 8
+>> Invalid get index 'OUTER_CONST' (on base: 'RefCounted (Inner)').

modules/gdscript/tests/scripts/analyzer/errors/outer_class_instance_constants_as_variant.gd

@@ -0,0 +1,9 @@
+class Outer:
+	const OUTER_CONST: = 0
+	class Inner:
+		pass
+
+func test() -> void:
+	var instance: = Outer.Inner.new()
+	var instance_v: Variant = instance
+	print(instance_v.OUTER_CONST)

modules/gdscript/tests/scripts/analyzer/errors/outer_class_instance_constants_as_variant.out

@@ -0,0 +1,6 @@
+GDTEST_RUNTIME_ERROR
+>> SCRIPT ERROR
+>> on function: test()
+>> analyzer/errors/outer_class_instance_constants_as_variant.gd
+>> 9
+>> Invalid get index 'OUTER_CONST' (on base: 'RefCounted (Inner)').