fix: docs/_klipper3d/mkdocs-requirements.txt to reduce vulnerabilities

The following vulnerabilities are fixed by pinning transitive dependencies:
- https://snyk.io/vuln/SNYK-PYTHON-JINJA2-8548181
- https://snyk.io/vuln/SNYK-PYTHON-JINJA2-8548987

docs/_klipper3d/mkdocs-requirements.txt

@@ -1,5 +1,5 @@
 # Python virtualenv module requirements for mkdocs
-jinja2==3.1.3
+jinja2==3.1.5
 mkdocs==1.2.4
 mkdocs-material==8.1.3
 mkdocs-simple-hooks==0.1.3