Add a 'check_redefinition' configuration attribute to the GNATcheck testing driver

Author: HugoGGuerrier

testsuite/drivers/gnatcheck_driver.py

@@ -101,6 +101,8 @@ class GnatcheckDriver(BaseDriver):
 
         - ``check_semantic`` (bool): Whether to add the ``--check-semantic``
           flag when running GNATcheck.
+        - ``check_redefinition`` (bool): Whether to add the
+          ``--check-redefinition`` flag when running GNATcheck.
         - ``rules`` (list[str]): A list of rules with their arguments, in the
           gnatcheck format.  Note that the list can be empty, and people can
           instead decide to pass rules via the project file.
@@ -531,6 +533,10 @@ def run_one_test(test_data: dict[str, any]) -> None:
             if test_data.get("check_semantic"):
                 args.append("--check-semantic")
 
+            # If required, add the "--check-redefinition" flag
+            if test_data.get("check_redefinition"):
+                args.append("--check-redefinition")
+
             # Add the rule directories
             for rule_dir in test_data.get("rules_dirs", []):
                 args.append(f"--rules-dir={rule_dir}")