Dumper: remove unused imports

Change-Id: I447c9697dbd631ab26358c193c274484e70a908d
Reviewed-by: Christian Stenger <christian.stenger@qt.io>

share/qtcreator/debugger/dumper.py

@@ -25,7 +25,6 @@
 
 import os
 import codecs
-import copy
 import collections
 import struct
 import sys
@@ -33,7 +32,6 @@ import base64
 import re
 import time
 import inspect
-import threading
 from utils import DisplayFormat, TypeCode
 
 try:

share/qtcreator/debugger/gdbbridge.py

@@ -35,7 +35,6 @@ import re
 import sys
 import struct
 import tempfile
-import types
 
 from dumper import DumperBase, Children, toInteger, TopLevelItem
 from utils import TypeCode