False positive `G307: Deferring unsafe method "Close" on type "*os.File" (gosec)` linting error

[atc0005]

False-positive error surfaced from an upgraded golangci-lint:

internal/config/file.go:35:2: G307: Deferring unsafe method "Close" on type "*os.File" (gosec)
	defer func() {
		if err := fh.Close(); err != nil {
			// Ignore "file already closed" errors
			if !errors.Is(err, os.ErrClosed) {
				log.Errorf(
					"loadConfigFile: failed to close file %q: %s",
					configFile,
					err.Error(),
				)
			}
		}
	}()
make: *** [Makefile:149: linting] Error 1
Error: Process completed with exit code 2.

Same problem as noted on atc0005/check-mail#234.