gh-38608: Add warning filter for DeprecationWarning while doc build
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Fixes #37664.
from the log of the doc build workflow of this PR,
```
[sagemath_doc_html-none] [spkg-install] sage --docbuild --no-pdf-links
reference/cryptography inventory
[sagemath_doc_html-none] [spkg-install] [cryptogra] Converting
`source_suffix = '.rst'` to `source_suffix = {'.rst':
'restructuredtext'}`.
[sagemath_doc_html-none] [spkg-install] [cryptogra] building
[inventory]: targets for 25 source files that are out of date
[sagemath_doc_html-none] [spkg-install] [cryptogra] updating
environment: [new config] 25 added, 0 changed, 0 removed
[sagemath_doc_html-none] [spkg-install] [cryptogra] The inventory file
is in ../../local/share/doc/sage/inventory/en/reference/cryptography.
[sagemath_doc_html-none] [spkg-install] sage --docbuild --no-pdf-links
reference/curves inventory
```
This PR is based on #38580 and replaces it. Thank @thecaligarmo for
allowing this arrangement.
### :memo: Checklist
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- [ ] I have updated the documentation and checked the documentation
preview.
### :hourglass: Dependencies
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URL: https://github.com/sagemath/sage/pull/38608
Reported by: Kwankyu Lee
Reviewer(s): Matthias Köppe
