Update the CI workflows to track the current major version trunk and
use the latest release in the build matrix, when tests are not run.

We cannot currently udate to 5.4 for the matrix used to run tests, but
some of the test dependencies don't support it.

As per ocaml/opam-repository#28683

Signed-off-by: Shon Feder <shon.feder@gmail.com>

* 'main' of github.com:/ocaml/dune: (147 commits)
  cram test: test only parameter flags in merlin generation
  fix(oxcaml): import eta-expansion changes from opam-repo (ocaml#12563)
  address review comments
  Mask the path to the stdlib
  fix(oxcaml): generate merlin config for library parameters
  fix(melange + include_qualified): track correct `.cmj` dependencies in emit (ocaml#12531)
  refactor: remove some unused code in [Path] (ocaml#12558)
  dep_rules: don't run (transitive) `ocamldep` on single module buildables (ocaml#12555)
  fix(pkg): ignore project settings for building packages
  test(pkg): reproduce ocaml#12131
  melange: add a test for module cycle checks (ocaml#12554)
  chore: lint check for new changes entries (ocaml#12553)
  feature(cram): allow for conflict detection (ocaml#12538)
  ci: update for ocaml 5.4 release (ocaml#12552)
  chore(script): generate changelog from structure (ocaml#12516)
  Reuse dependencies between project and tools (ocaml#12526)
  Introduce Io.overwrite_file
  test: fix dune install requiring a mandir
  Enable package management for more tests
  Add a `dune tools env` command to add dev tools to PATH (ocaml#12521)
  ...

Update the CI workflows to track the current major version trunk and
use the latest release in the build matrix, when tests are not run.

We cannot currently udate to 5.4 for the matrix used to run tests, but
some of the test dependencies don't support it.

As per ocaml/opam-repository#28683

Signed-off-by: Shon Feder <shon.feder@gmail.com>