tests: add a regression test

Author: zerbina

tests/lang_callable/overload/toverload_resolution_ast_corruption_bug.nim

@@ -0,0 +1,18 @@
+discard """
+  description: '''
+    Regression test for argument expressions in call expressions passed to
+    untyped parameters being typed when there exists another overload accepting
+    a typed parameter in the same position.
+  '''
+"""
+
+proc test1(x: int, y: int) =
+  discard
+
+proc test2(x: int, y: int) =
+  discard
+
+template test2(x, y: untyped) =
+  doAssert astToStr(x) == "test1(1 + 3, 2)"
+
+test2(test1(1 + 3, 2), 1)