Bump pymdown-extensions from 10.21.2 to 10.21.3 (#183)

* Bump pymdown-extensions from 10.21.2 to 10.21.3

Bumps [pymdown-extensions](https://github.com/facelessuser/pymdown-extensions) from 10.21.2 to 10.21.3.
- [Release notes](https://github.com/facelessuser/pymdown-extensions/releases)
- [Commits](facelessuser/pymdown-extensions@10.21.2...10.21.3)

---
updated-dependencies:
- dependency-name: pymdown-extensions
  dependency-version: 10.21.3
  dependency-type: indirect
...

Signed-off-by: dependabot[bot] <support@github.com>

* chore: bump idna to >=3.15 to fix CVE-2026-45409

idna 3.11 is vulnerable to denial-of-service via specially crafted
inputs to idna.encode(). Version 3.15 extends the fix to cover all
affected code paths.

Co-authored-by: aieng-bot <aieng-bot@vectorinstitute.ai>

---------

Signed-off-by: dependabot[bot] <support@github.com>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>
Co-authored-by: aieng-bot[bot] <aieng-bot@vectorinstitute.ai>

Author: dependabot[bot]

pyproject.toml

@@ -35,6 +35,8 @@ dependencies = [
     "meds-transforms>=0.6.1",
     # urllib3>=2.7.0 fixes CVE-2026-44431 and CVE-2026-44432
     "urllib3>=2.7.0",
+    # idna>=3.15 fixes CVE-2026-45409
+    "idna>=3.15",
 ]
 
 [project.optional-dependencies]