chore(deps): bump jinja2 in /rootfs/usr/local/lib/web/backend

Bumps [jinja2](https://github.com/pallets/jinja) from 2.10.3 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@2.10.3...2.11.3) Signed-off-by: dependabot[bot] <support@github.com>

Author: dependabot[bot]

rootfs/usr/local/lib/web/backend/requirements.txt

@@ -9,7 +9,7 @@ gevent-websocket==0.10.1
 greenlet==0.4.15
 idna==2.8
 itsdangerous==1.1.0
-Jinja2==2.10.3
+Jinja2==2.11.3
 MarkupSafe==1.1.1
 meld3==2.0.0
 requests==2.22.0