Replace jamesponddotco/xstd-go with go.cipher.host/x

[jamesponddotco]

What does this PR do?

Replace the dependency on git.sr.ht/~jamesponddotco/xstd-go which I wrote but maintain alone, with go.cipher.host/x, a fork of sorts that can be maintained by the team.

Review checklist

Before submitting your PR, please review the following:

• I have read the CONTRIBUTING.md file.
• My changes are focused and address a single concern.
• I have added/updated tests that prove my fix is effective or that my feature works.
• New and existing tests pass locally with my changes.
• I have added necessary documentation or made changes to documentation (if appropriate).
• My changes generate no new warnings or errors.
• My code follows the code style of this project.

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• The contribution is my own original work.
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