[Nullable] WIP: Nullable test cases.

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

@@ -1,2 +1,2 @@
 GDTEST_ANALYZER_ERROR
-Potentially unsafe for nullable "foo.c?[0]" to call "begins_with()".
+Potentially unsafe for nullable "<not implemented>" to call "begins_with()".

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

@@ -1,2 +1,2 @@
 GDTEST_ANALYZER_ERROR
-Potentially unsafe for nullable "foo?.b" to call "banana()".
+Potentially unsafe for nullable "b" to call "banana()".

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

@@ -1,2 +1,2 @@
 GDTEST_ANALYZER_ERROR
-Potentially unsafe to access nullable cast expression "nullable_instance as A?" with attribute "foo".
+Potentially unsafe to access nullable cast expression "<not implemented>" with attribute "foo".

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

@@ -1,2 +1,2 @@
 GDTEST_ANALYZER_ERROR
-Potentially unsafe for the nullable cast expression "nullable_string as String?" to call "begins_with()".
+Potentially unsafe for the nullable cast expression "<not implemented>" to call "begins_with()".

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

@@ -1,2 +1,2 @@
 GDTEST_ANALYZER_ERROR
-Potentially unsafe for the nullable expression "instance.arr" to be used in a for-loop.
+Potentially unsafe for the nullable expression "arr" to be used in a for-loop.

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

@@ -2,4 +2,5 @@ class A:
     var b: String
 func test():
     var a: A? = A.new()
-    a?.b = "123"
+    a?.b = "123"
+    print(a?.b)

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

@@ -1,2 +1,2 @@
-GDTEST_ANALYZER_ERROR
-The left-hand side of an assignment expression may not contain a nullable access operator ("?.").
+GDTEST_OK
+123

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

@@ -1,2 +1,2 @@
 GDTEST_ANALYZER_ERROR
-Potentially unsafe to access nullable "foobar[0]" with attribute "bar".
+Potentially unsafe to access nullable "<not implemented>" with attribute "bar".

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

@@ -1,2 +1,2 @@
 GDTEST_ANALYZER_ERROR
-Potentially unsafe for nullable "foo[0]" to call "hey()".
+Potentially unsafe for nullable "<not implemented>" to call "hey()".

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

@@ -1,2 +1,2 @@
 GDTEST_ANALYZER_ERROR
-Potentially unsafe for the nullable expression "a_instance.get_nullable_instance()?.index" to be used as an index.
+Potentially unsafe for the nullable expression "index" to be used as an index.