write_literal: Fix index of the remaining positional arguments

[koka831]

• fixes cargo clippy --fix broken for positional arguments #10128
• clippy --fix replaces multiple warnings at once
  e.g.)

  writeln!(v, "{0} {1}", "hello", "world");
  // before: `writeln!(v, "hello {1}", "world");`
  // now: `writeln!(v, "hello world");`

changelog: [print_literal], [write_literal]: Now handles positional argument properly

[rustbot]

r? @llogiq

(rustbot has picked a reviewer for you, use r? to override)

[llogiq]

Thanks, this looks good to me. I wonder whether we can also inline other literals beside str. For example the last example could well just write the "2", "3" and "4" literals as part of the format string. Anyway,

@bors r+

[bors]

📌 Commit b413bf6 has been approved by llogiq

It is now in the queue for this repository.

[bors]

⌛ Testing commit b413bf6 with merge d18d01a...

[bors]

☀️ Test successful - checks-action_dev_test, checks-action_remark_test, checks-action_test
Approved by: llogiq
Pushing d18d01a to master...

[koka831]

Found that Lit::Int (which is now Lit::Integer) and Lit::Float had been ignored by #6335.

I'm not sure should we handle this (at least it can be relaxed by checking lit.chars().all(|c| c.is_ascii_digit())).