github.com/golangci/golangci-lint-action のバージョンが v5 になっているのに気づいた。最新のスクリプトはこんな感じらしい。

name: golangci-lint
on:
  push:
    branches:
      - main
      - master
  pull_request:

permissions:
  contents: read
  # Optional: allow read access to pull request. Use with `only-new-issues` option.
  # pull-requests: read

jobs:
  golangci:
    name: lint
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v4
      - uses: actions/setup-go@v5
        with:
          go-version: '1.21'
      - name: golangci-lint
        uses: golangci/golangci-lint-action@v5
        with:
          # Require: The version of golangci-lint to use.
          # When `install-mode` is `binary` (default) the value can be v1.2 or v1.2.3 or `latest` to use the latest version.
          # When `install-mode` is `goinstall` the value can be v1.2.3, `latest`, or the hash of a commit.
          version: v1.57

          # Optional: working directory, useful for monorepos
          # working-directory: somedir

          # Optional: golangci-lint command line arguments.
          #
          # Note: By default, the `.golangci.yml` file should be at the root of the repository.
          # The location of the configuration file can be changed by using `--config=`
          # args: --timeout=30m --config=/my/path/.golangci.yml --issues-exit-code=0 

          # Optional: For pull request only, show only new issues. The default value is `false`.
          # only-new-issues: true

          # Optional: if set to true, then all caching functionality will be completely disabled,
          #           takes precedence over all other caching options.
          # skip-cache: true

          # Optional: if set to true, caches will not be saved, but they may still be restored,
          #           subject to other options
          # skip-save-cache: true

          # Optional: The mode to install golangci-lint. It can be 'binary' or 'goinstall'.
          # install-mode: "goinstall"

って actions/checkout が v4 に actions/setup-go が v5 になっとるがな。これは自パッケージの GitHub Actions スクリプトを全面的に見直さんといかんか...

actions/setup-go のバージョンが v5 になってる