`dtolnay/rust-toolchain` is not a dependency in the sense Dependabot
means: it is versioned by the Rust release it installs, and the tag we
pin is the toolchain CI is pinned to on purpose — precommit.sh runs the
same one locally, so a lint that passes on a developer's newer default
cannot pass CI by accident.
Read as semver, those tags produced a 1.97.0 -> 1.100.0 proposal, a Rust
version that does not exist. Every such PR 404s on toolchain download
across all eight repos and regenerates weekly: eight permanently-red PRs
that promote.yml then has to special-case when it decides whether dev is
green.
freemkv already carries this ignore; this is the same block in the other
seven, so the fleet stays uniform. Bumping the toolchain stays a
deliberate, all-eight-repos change made by hand together with
precommit.sh.
Matthew Jackson
313460c97f