Ignore warnings in included xtensor library

[james-ward]

Basic Info

Info	Please fill out this column
Ticket(s) this addresses	Related to #4265
Primary OS tested on	(Ubuntu, MacOS, Windows)
Robotic platform tested on	Compile only
Does this PR contain AI generated software?	No

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Description of contribution in a few bullet points

• Suppress warnings (which are then treated as errors) from upstream xtensor library

Description of documentation updates required from your changes

• None

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Future work that may be required in bullet points

• None for this particular problem

For Maintainers:

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