Fix the test output, now that escapes in repr() of string and Unicode

are different (Ping didn't test this).

Lib/test/output/test_mmap

@@ -2,13 +2,13 @@ test_mmap
 <type 'mmap'>
   Position of foo: 1.0 pages
   Length of file: 2.0 pages
-  Contents of byte 0: '\000'
-  Contents of first 3 bytes: '\000\000\000'
+  Contents of byte 0: '\x00'
+  Contents of first 3 bytes: '\x00\x00\x00'
 
   Modifying file's content...
   Contents of byte 0: '3'
-  Contents of first 3 bytes: '3\000\000'
-  Contents of second page: '\000foobar\000'
+  Contents of first 3 bytes: '3\x00\x00'
+  Contents of second page: '\x00foobar\x00'
   Regex match on mmap (page start, length of match): 1.0 6
   Seek to zeroth byte
   Seek to 42nd byte

Lib/test/output/test_rotor

 test_rotor
-'\265q\220\243\350IT\321\007\332\035\334\337'
-'\033>k(\037\212,\201\313\237\342'
+'\xb5q\x90\xa3\xe8IT\xd1\x07\xda\x1d\xdc\xdf'
+'\x1b>k(\x1f\x8a,\x81\xcb\x9f\xe2'
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