GitHub Actions now emits "Node.js 20 actions are deprecated" warnings:
actions are forced to Node.js 24 by default starting 2026-06-16, and
Node.js 20 is removed from the runners on 2026-09-16. Update every
JavaScript action referenced by the workflows and the local composite
actions to the lowest release that runs on Node.js 24:
actions/checkout v4 -> v5
actions/checkout (SHA pin) v4.1.7 -> v5
actions/upload-artifact v4 -> v6 (v5 still Node.js 20)
actions/download-artifact v4 -> v7 (v5/v6 still Node.js 20)
actions/cache[/restore|/save] v4 -> v5
actions/setup-python v5 -> v6
actions/github-script v7 -> v8
docker/setup-buildx-action v3 -> v4
docker/build-push-action v5 -> v7 (v6 still Node.js 20)
docker/login-action v3 -> v4
microsoft/setup-msbuild v2 -> v3
open-watcom/setup-watcom v0 -> v1
Actions already running on Node.js 24 (jwlawson/actions-setup-cmake,
shogo82148/actions-setup-perl, msys2/setup-msys2, dorny/paths-filter)
are left unchanged. These bumps are runtime-only; no workflow uses an
input or output removed by the new majors, and v4-format artifacts
remain compatible across the upload v6 / download v7 backends.