docs: Fix the pacman-like interface example link
- Basic demo: [derive](demo.md)
- Key-value pair arguments: [derive](keyvalue_derive.md)
- git-like interface: [builder](git.md), [derive](git_derive.md)
-- pacman-like interface: [builder](git.md)
+- pacman-like interface: [builder](pacman.md)
- Escaped positionals with `--`: [builder](escaped_positional.md), [derive](escaped_positional_derive.md)
- Multi-call
- busybox: [builder](multicall_busybox.md)
