chore: bump squidfunk/mkdocs-material in /docs (#2127)

Bumps squidfunk/mkdocs-material from `1a4e939` to `209b62d`.

---
updated-dependencies:
- dependency-name: squidfunk/mkdocs-material
  dependency-version: 209b62dd9530163cc5cf9a49853b5bb8570ffb3f3b5fe4eadc1d319bbda5ce2f
  dependency-type: direct:production
...

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Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

Author: dependabot[bot]

docs/Dockerfile

@@ -1,4 +1,4 @@
-FROM squidfunk/mkdocs-material@sha256:1a4e939cfd62b90943b6a829eb8544933e4e94eab18b8ca1d0f912fa9a532c37
+FROM squidfunk/mkdocs-material@sha256:209b62dd9530163cc5cf9a49853b5bb8570ffb3f3b5fe4eadc1d319bbda5ce2f
 
 COPY requirements.txt /tmp/
 RUN pip install --require-hashes -r /tmp/requirements.txt