Fix proxy-pass url

[jukefr]

Causing issues with npm registry (and probably more) See https://github.com/go-gitea/gitea/issues/21407 and specifically https://github.com/go-gitea/gitea/issues/21407#issuecomment-1420975465

Problem

See https://github.com/YunoHost-Apps/gitea_ynh/issues/73

Solution

Removing the slash

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)

[Josue-T]

!testme

[yunohost-bot]

Fingers crossed!

[jukefr]

not sure why subpath install seems to make this go wrong i dont know nginx well enough so i'll let people who do handle this i know for subdomain install this seems to work fine