Small fdiv argument fixes

[rundel]

Description

These are just minor fixes to fenced div argument issues I came across in some of the test files.

seismic-monitoring-stations.qmd - missing . from the note class

2024/05/06/9582.qmd - identifier should be before class

2025/03/21/issue-12344.qmd - class should be before key-value

I don't think any of the above are meant to test this pandoc requirement and so should be safe to correct.

Checklist

I don't believe any of the below are applicable in this case.

• filed a contributor agreement.
• referenced the GitHub issue this PR closes
• updated the appropriate changelog in the PR
• ensured the present test suite passes
• added new tests
• created a separate documentation PR in Quarto's website repo and linked it to this PR

[posit-snyk-bot]

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[cscheid]

Thank you. These look good, and I'm happy this syntax appears to match what we're going to start enforcing more directly with https://github.com/quarto-dev/quarto-markdown