Update nginx.conf

[rodinux]

resolve issue #23 for upgrade libreto

Problem

• Upgrading the app broke the css and the links to the wiki created

Solution

• Editing the nginx libreto.conf with value as the preview commit b9b3687

PR Status

• [x] Code finished and ready to be reviewed/tested
• [x] The fix/enhancement were manually tested (if applicable)

Automatic tests

Automatic tests can be triggered on https://ci-apps-dev.yunohost.org/ after creating the PR, by commenting "!testme", "!gogogadgetoci" or "By the power of systemd, I invoke The Great App CI to test this Pull Request!". (N.B. : for this to work you need to be a member of the Yunohost-Apps organization)

[rodinux]

!testme

[yunohost-bot]

Fingers crossed!

[rodinux]

This fix issue #23