Antoine Stevan 92c1051143
fix the span of the global std help item (#9184)
related to 
- #9101
- #9039

# Description
i actually forgot to fix in #9039 the new "*item*" introduced by
#9101... 👀
there it is 😇 

# User-facing changes
going from
```
> std help git-commiteuwqi
Help pages from external command git-commiteuwqi:
No manual entry for git-commiteuwqi
Error:
  × std::help::item_not_found
     ╭─[help:721:1]
 721 │
 722 │     let item = ($item | str join " ")
     ·     ─┬─
     ·      ╰── item not found
 723 │
     ╰────
```
to
```
> std help git-commiteuwqi
Help pages from external command git-commiteuwqi:
No manual entry for git-commiteuwqi
Error:
  × std::help::item_not_found
   ╭─[entry #2:1:1]
 1 │ std help git-commiteuwqi
   ·          ───────┬───────
   ·                 ╰── item not found
   ╰────
```

# Tests + Formatting
- 🟢 `toolkit fmt`
- 🟢 `toolkit clippy`
-  `toolkit test`
-  `toolkit test stdlib`

# After Submitting
```
$nothing
```
2023-05-12 20:30:38 +02:00
..
2023-05-10 19:18:42 +02:00