[lldbsuite] Remove the DumpFormatter

This formatter is never used or referenced.

lldb/packages/Python/lldbsuite/test_event/formatter/dump_formatter.py

@@ -1,22 +0,0 @@
-"""
-Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
-See https://llvm.org/LICENSE.txt for license information.
-SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
-"""
-
-from __future__ import print_function
-from __future__ import absolute_import
-
-# System modules
-import pprint
-
-# Our modules
-from .results_formatter import ResultsFormatter
-
-
-class DumpFormatter(ResultsFormatter):
-    """Formats events to the file as their raw python dictionary format."""
-
-    def handle_event(self, test_event):
-        super(DumpFormatter, self).handle_event(test_event)
-        self.out_file.write("\n" + pprint.pformat(test_event) + "\n")