[fix] Missing cache

[zamentur]

Problem

Some user lost data when they remove /reinstall onlyoffice (some cache data could contains files) Here i suggest to backup the cache directory and to restore it

PR Status

• [x] Code finished and ready to be reviewed/tested
• [ ] 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)

[zamentur]

!testme

[yunohost-bot]

:stuck_out_tongue_winking_eye:

[Gredin67]

!testme

[yunohost-bot]

:stuck_out_tongue_winking_eye:

[Gredin67]

!testme

[yunohost-bot]

May the CI gods be with you!