`lint_groups_priority` clippy lint seems to misattribute lints to groups

I’m using the following Cargo.toml:

[package]
name = "testing"
version = "0.1.0"
edition = "2021"

[lints.clippy]
lint_groups_priority = "warn"

[lints.rust]
keyword_idents = "deny"
macro_use_extern_crate = "deny"
rust_2018_idioms = "deny"
single_use_lifetimes = "deny"

Running cargo clippy produces two warnings here:

warning: lint group `keyword_idents` has the same priority (0) as a lint
  --> Cargo.toml:10:1
   |
10 | keyword_idents = "deny"
   | ^^^^^^^^^^^^^^   ------ has an implicit priority of 0
11 | macro_use_extern_crate = "deny"
   | ---------------------- has the same priority as this lint
   |
   = note: the order of the lints in the table is ignored by Cargo
   = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#lint_groups_priority
   = note: requested on the command line with `-W clippy::lint-groups-priority`
help: to have lints override the group set `keyword_idents` to a lower priority
   |
10 | keyword_idents = { level = "deny", priority = -1 }
   |                  ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

warning: lint group `rust_2018_idioms` has the same priority (0) as a lint
  --> Cargo.toml:12:1
   |
12 | rust_2018_idioms = "deny"
   | ^^^^^^^^^^^^^^^^   ------ has an implicit priority of 0
13 | single_use_lifetimes = "deny"
   | -------------------- has the same priority as this lint
   |
   = note: the order of the lints in the table is ignored by Cargo
   = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#lint_groups_priority
help: to have lints override the group set `rust_2018_idioms` to a lower priority
   |
12 | rust_2018_idioms = { level = "deny", priority = -1 }
   |                    ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

While making the proposed changes silences the warnings, these look like false positives. According to documentation, single_use_lifetimes isn’t part of rust_2018_idioms, and keyword_idents isn’t a group at all.

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rustc --version --verbose:

rustc 1.81.0-nightly (d0227c6a1 2024-06-11)
binary: rustc
commit-hash: d0227c6a19c2d6e8dceb87c7a2776dc2b10d2a04
commit-date: 2024-06-11
host: x86_64-unknown-linux-gnu
release: 1.81.0-nightly
LLVM version: 18.1.7

Reproduce the report with the provided Cargo.toml using cargo clippy and the listed rustc 1.81.0-nightly version. Trace how lint_groups_priority identifies groups and compare its attribution with the documented membership of keyword_idents and rust_2018_idioms. Done means the lint no longer reports these false positives while still detecting genuine priority conflicts.