[Support] Fix an invalid character escaping in string literal (unittest).

[etienneb]

Summary

A character within a string literal is not escaped correctly.
In this case, there is no semantic change because the invalid character turn out to be NUL anyway.

note: "\0x12" is equivalent to {0, 'x', '1', '2'} and not { 12 }.

This issue was found by clang-tidy.

[rnk]

Lgtm I suppose the test worked fine because it still found the right magic bytes.

unittests/Support/Path.cpp

 const char coff_import_library[] = "\x00\x00\xff\xff....";
 const char elf_relocatable[] = { 0x7f, 'E', 'L', 'F', 1, 2, 1, 0, 0,
                                  0,    0,   0,   0,   0, 0, 0, 0, 1 };
-const char macho_universal_binary[] = "\xca\xfe\xba\xbe...\0x00";
+const char macho_universal_binary[] = "\xca\xfe\xba\xbe...\x00";
 const char macho_object[] =
     "\xfe\xed\xfa\xce........\x00\x00\x00\x01............";
 const char macho_executable[] =