chore(deps): update urfave/cli/v3 to v3.9.0 (#37863)

Updates `github.com/urfave/cli/v3` to
[v3.9.0](https://github.com/urfave/cli/releases/tag/v3.9.0) and removes
the renovate pin now that
[urfave/cli#2319](https://github.com/urfave/cli/pull/2319) (the `-c`
help flag parsing fix) is merged.

v3.9.0 prepends the default command name to the root command's args,
which broke the old `Root().Args()` check in `isValidDefaultSubCommand`.
It now uses the command's own `Args()`.

Behavior change: `./gitea web <extra-positional-arg>` now errors with
`unknown command` instead of starting the web server and ignoring the
trailing arg. `web` takes no positional args, so this is stricter (and
arguably more correct) input handling. The intended `./gitea bad-cmd`
rejection is unchanged.

---
This PR was written with the help of Claude Opus 4.7

---------

Co-authored-by: Claude (Opus 4.7) <noreply@anthropic.com>
Co-authored-by: Nicolas <bircni@icloud.com>

go.sum

@@ -719,8 +719,8 @@ github.com/unknwon/com v1.0.1 h1:3d1LTxD+Lnf3soQiD4Cp/0BRB+Rsa/+RTvz8GMMzIXs=
 github.com/unknwon/com v1.0.1/go.mod h1:tOOxU81rwgoCLoOVVPHb6T/wt8HZygqH5id+GNnlCXM=
 github.com/urfave/cli-docs/v3 v3.1.0 h1:Sa5xm19IpE5gpm6tZzXdfjdFxn67PnEsE4dpXF7vsKw=
 github.com/urfave/cli-docs/v3 v3.1.0/go.mod h1:59d+5Hz1h6GSGJ10cvcEkbIe3j233t4XDqI72UIx7to=
-github.com/urfave/cli/v3 v3.6.1 h1:j8Qq8NyUawj/7rTYdBGrxcH7A/j7/G8Q5LhWEW4G3Mo=
-github.com/urfave/cli/v3 v3.6.1/go.mod h1:ysVLtOEmg2tOy6PknnYVhDoouyC/6N42TMeoMzskhso=
+github.com/urfave/cli/v3 v3.9.0 h1:AV9lIiPv3ukYnxunaCUsHnEozptYmDN2F0+yWqLMn/c=
+github.com/urfave/cli/v3 v3.9.0/go.mod h1:ysVLtOEmg2tOy6PknnYVhDoouyC/6N42TMeoMzskhso=
 github.com/willf/bitset v1.1.10/go.mod h1:RjeCKbqT1RxIR/KWY6phxZiaY1IyutSBfGjNPySAYV4=
 github.com/wneessen/go-mail v0.7.3 h1:g3DravXC5SMlVdboFrQA8Jx95A8sOzoBeS5F+vzNRK0=
 github.com/wneessen/go-mail v0.7.3/go.mod h1:QGhBX0yNbc1J+Mkjcu7z2rpj4B4l+BmDY8gYznPC9sk=