First fixes; conv and format_spec still not working

Author: lysnikolaou

Parser/action_helpers.c

@@ -1491,7 +1491,7 @@ expr_ty _PyPegen_interpolation(Parser *p, expr_ty expression, Token *debug, Resu
     int conversion_val = _get_interpolation_conversion(p, debug, conversion, format);
     if (conversion_val >= 0) {
         expr_ty conv = (expr_ty) conversion->result;
-        constant convstr = PyUnicode_FromObject(conv->v.Name.id);
+        convstr = PyUnicode_FromObject(conv->v.Name.id);
         if (convstr == NULL) {
             return NULL;
         }

Python/ast.c

@@ -371,7 +371,7 @@ validate_expr(struct validator *state, expr_ty exp, expr_context_ty ctx)
     case Interpolation_kind:
         if (validate_expr(state, exp->v.Interpolation.value, Load) == 0)
             return 0;
-        if (exp->v.FormattedValue.format_spec) {
+        if (exp->v.Interpolation.format_spec) {
             ret = validate_expr(state, exp->v.Interpolation.format_spec, Load);
             break;
         }