avoid sanitizer warning unsigned integer overflow

[wayne-arnold-adsk]

avoid sanitizer warning of unsigned integer overflow

src/Components/ExternalLibraries/OpenImageIO/install/include/OpenImageIO/string_view.h:252:43: runtime error: unsigned integer overflow: 0 - 17 cannot be represented in type 'unsigned long'
#0 0x10d0adf61 in OpenImageIOMaya_v2_4::basic_string_view<char, std::__1::char_traits >::compare(OpenImageIOMaya_v2_4::basic_string_view<char, std::__1::char_traits >) const string_view.h:252

Description

Tests

Checklist:

• I have read the contribution guidelines.
• If this is more extensive than a small change to existing code, I
  have previously submitted a Contributor License Agreement
  (individual, and if there is any way my
  employers might think my programming belongs to them, then also
  corporate).
• I have updated the documentation, if applicable.
• I have ensured that the change is tested somewhere in the testsuite
  (adding new test cases if necessary).
• My code follows the prevailing code style of this project.

[wayne-arnold-adsk]

I don't see why my change would fail:
CI, Attempt #2 / Ubuntu bleeding edge gcc12 C++20 py3.10 OCIO/libtiff/exr-master boost1.74 avx2

[lgritz]

I don't think the bleeding edge failure is related to you at all, I'm seeing that failure across many PRs and scheduled CI runs. I think, actually, that maybe the runners got a gcc12 update and something that used to work is now warning with the new compiler. Something like that. I will address it separately.

[lgritz]

LGTM, thanks for the fix!