Bump jinja2 from 2.10.1 to 2.11.3 in /docs

Bumps [jinja2](https://github.com/pallets/jinja) from 2.10.1 to 2.11.3.
- [Release notes](https://github.com/pallets/jinja/releases)
- [Changelog](https://github.com/pallets/jinja/blob/master/CHANGES.rst)
- [Commits](pallets/jinja@2.10.1...2.11.3)

Signed-off-by: dependabot[bot] <[email protected]>

Author: dependabot[bot]

docs/requirements.txt

@@ -27,7 +27,7 @@ idna==2.8
 imagesize==0.7.1
 incremental==17.5.0
 ipaddress==1.0.16
-Jinja2==2.10.1
+Jinja2==2.11.3
 jsonpatch==1.15
 jsonpointer==1.10
 jsonschema==2.6.0