Corrects submodule schema references identified in #1883

[Compton-US]

Committer Notes

Fixes #1883 - Broken links to metaschema submodule content (should be metaschema-xslt + changed paths)

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[aj-stein-nist]

Thanks for this PR and underlining the severity in the issue. I will review this after sprint review.

[aj-stein-nist]

Apologies for the delay on this. This looks good to me and thanks for touching this up.