Bump mkdocs-material from 9.6.21 to 9.6.23 in /buildenv

Bumps [mkdocs-material](https://github.com/squidfunk/mkdocs-material) from 9.6.21 to 9.6.23.
- [Release notes](https://github.com/squidfunk/mkdocs-material/releases)
- [Changelog](https://github.com/squidfunk/mkdocs-material/blob/master/CHANGELOG)
- [Commits](squidfunk/mkdocs-material@9.6.21...9.6.23)

---
updated-dependencies:
- dependency-name: mkdocs-material
  dependency-version: 9.6.23
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

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

Author: dependabot[bot]

buildenv/requirements.txt

@@ -42,11 +42,6 @@ hjson==3.1.0
     #   super-collections
 idna==3.7
     # via requests
-importlib-metadata==8.7.0
-    # via
-    #   markdown
-    #   mkdocs
-    #   mkdocs-get-deps
 jinja2==3.1.6
     # via
     #   mkdocs
@@ -74,7 +69,7 @@ mkdocs-get-deps==0.2.0
     # via mkdocs
 mkdocs-macros-plugin==1.4.0
     # via -r requirements.in
-mkdocs-material==9.6.21
+mkdocs-material==9.6.23
     # via -r requirements.in
 mkdocs-material-extensions==1.3
     # via mkdocs-material
@@ -119,5 +114,3 @@ urllib3==2.5.0
     # via requests
 watchdog==2.2.1
     # via mkdocs
-zipp==3.21.0
-    # via importlib-metadata