chore: modify justfile to use internal function instead of which

[ulic-youthlic]

as the title: modify justfile to use internal function.

[pk5ls20]

It appears that when running just info in git bash, the output has issues, but the functionality of just check is not affected.

$ just info
JUST PATH: C:Userspk5ls.cargobinjust.exe
GIT PATH: C:Program FilesGitmingw64bingit.exe
CARGO PATH: C:Userspk5ls.cargobincargo.exe
GREP PATH: C:Program FilesGitusrbingrep.exe
XARGS PATH: C:Program FilesGitusrbinxargs.exe
TYPOS PATH: C:Userspk5ls.cargobintypos.exe
DENO PATH: C:Userspk5lsscoopshimsdeno.exe
TAPLO PATH: C:Userspk5ls.cargobintaplo.exe
SHFMT PATH: C:Userspk5lsgobinshfmt.exe