opam-repo-ci

Remove DuneLowerBoundMissing linter variant (#433) * Remove DuneLowerBoundMissing linter variant Remove the linter check for `dune` lower bound, and handle this with more general and accurate error reporting on the dune version constraint checks. --------- Co-authored-by: Shon Feder <shon.feder@gmail.com>

Revert to using opam 2.3

Improve parse errors in linting check We had an error recently in CI that was tricky to figure out because it was unclear what kind of error it was (e.g., due to parsing versions or bad format or something else), and which position it was arising from in the file. This improvement reuses `opam-format`'s error reporting logic to give a more useful errors messages, that includes the position of the error.

Remove double checks for source archive checksums The opam lint with `--check-upstream` ensures that the checksums for the upstream archive is correct. But, we also have a separate `check_checksums` that also ensures this. This commit removes the double checksum check in the default case, but keeps the check when running with only "--checks opam-file". This partially addresses #400.

ocaml-{base-compiler,compiler} trigger addition of --update-invariants Previously, only ocaml-variants packages would trigger addition of `--update-invariants` when reinstalling the packages. This commit adds ocaml-compiler and ocaml-base-compiler packages to the list of packages that have this behavior. Closes #408

lower-bounds: run the check with the opam-repository-archive on Currently the opam-repository will test the lower bound on most latest versions of packages. And even though most cases are avoided by the fact that we add upper bounds to all archived packages, the new packages may still be compatible and co-installable. So we should keep checking the lower bounds with the whole database to ensure that the metadata on the opam-repository remains consistent