Add an option to the logger to immediately fatal on first error

* This is mostly useful for some of the tests that want to be able to run and
  accumulate multiple errors, but while debugging we want an exception to catch.

util/test/rdtest/logging.py

@@ -32,6 +32,7 @@ class TestLogger:
         self.ctx_callback: Callable[[], None] | None = None
         self.outputs: List[IO[str]] = [sys.stdout]
         self.failed = False
+        self.fast_fail = False
         self.section_failed = False
         self.logged_exception = False
         self.mutex = threading.Lock()
@@ -158,6 +159,9 @@ class TestLogger:
 
         self.rawprint("!! " + message)
 
+        if self.fast_fail:
+            raise TestFailureException("Forcing failure")
+
     def failure(self, ex: Exception):
         if self.logged_exception:
             return