Fix version of golangci-lint

[adrianchiris]

currently the workflow will use latest version which is a moving target.

newer versions may cause ci failures due to new checks added.

[adrianchiris]

Example run on main branch with golangci-lint 1.56.1 (which was released a few days ago):

$ docker run --rm -v $(p
wd):/app -w /app golangci/golangci-lint:v1.56.1 golangci-lint run -v
level=info msg="[config_reader] Config search paths: [./ /app / /root]"
level=info msg="[config_reader] Used config file .golangci.yml"
level=info msg="[lintersdb] Active 18 linters: [contextcheck durationcheck gci ginkgolinter gocritic gofumpt gosimple govet ineffassign misspell nonamedreturns predeclared revive staticcheck unconvert unparam unused wastedassign]"
level=info msg="[loader] Go packages loading at mode 575 (exports_file|files|name|types_sizes|compiled_files|deps|imports) took 13.015389872s"
level=info msg="[runner/filename_unadjuster] Pre-built 0 adjustments in 24.441516ms"
level=info msg="[linters_context/goanalysis] analyzers took 2m5.23978475s with top 10 stages: buildir: 30.852740276s, buildssa: 10.34766137s, wastedassign: 10.290351335s, the_only_name: 10.098184443s, unparam: 3.534524563s, gocritic: 3.016104395s, gofumpt: 2.996833309s, misspell: 2.490761523s, gci: 2.10147502s, S1038: 1.789768904s"
level=info msg="[runner/max_same_issues] 11/14 issues with text \"unused-parameter: parameter 'netNS' seems to be unused, consider removing or renaming it as _\" were hidden, use --max-same-issues"
level=info msg="[runner/max_same_issues] 7/10 issues with text \"File is not `gofumpt`-ed\" were hidden, use --max-same-issues"
level=info msg="[runner/max_same_issues] 2/5 issues with text \"unused-parameter: parameter 'n' seems to be unused, consider removing or renaming it as _\" were hidden, use --max-same-issues"
level=info msg="[runner] Issues before processing: 324, after processing: 9"
level=info msg="[runner] Processors filtering stat (out/in): uniq_by_line: 29/29, path_shortener: 9/9, severity-rules: 9/9, filename_unadjuster: 324/324, skip_dirs: 324/324, exclude-rules: 32/324, max_from_linter: 9/9, path_prettifier: 324/324, identifier_marker: 324/324, nolint: 29/32, source_code: 9/9, path_prefixer: 9/9, cgo: 324/324, autogenerated_exclude: 324/324, exclude: 324/324, diff: 29/29, max_per_file_from_linter: 29/29, max_same_issues: 9/29, fixer: 9/9, sort_results: 9/9, skip_files: 324/324"
level=info msg="[runner] processing took 146.409956ms with stages: autogenerated_exclude: 95.452153ms, nolint: 22.711874ms, source_code: 9.860602ms, exclude-rules: 8.105378ms, identifier_marker: 7.926064ms, path_prettifier: 1.609905ms, skip_dirs: 452.601µs, max_same_issues: 153.366µs, cgo: 68.903µs, filename_unadjuster: 34.333µs, uniq_by_line: 12.682µs, path_shortener: 8.754µs, max_from_linter: 5.794µs, max_per_file_from_linter: 3.068µs, fixer: 881ns, severity-rules: 846ns, sort_results: 777ns, diff: 616ns, path_prefixer: 474ns, skip_files: 444ns, exclude: 441ns"
level=info msg="[runner] linters took 7.382723065s with stages: goanalysis_metalinter: 7.236036046s"
plugins/main/dummy/dummy.go:139: File is not `gofumpt`-ed (gofumpt)

plugins/main/dummy/dummy.go:168: File is not `gofumpt`-ed (gofumpt)

plugins/meta/sbr/main.go:69: File is not `gofumpt`-ed (gofumpt)

plugins/main/dummy/dummy_test.go:374:27: unused-parameter: parameter 'netNS' seems to be unused, consider removing or renaming it as _ (revive)
                        _ = originalNS.Do(func(netNS ns.NetNS) error {
                                               ^
plugins/main/vlan/vlan_test.go:502:29: unused-parameter: parameter 'netNS' seems to be unused, consider removing or renaming it as _ (revive)
                                        _ = originalNS.Do(func(netNS ns.NetNS) error {
                                                               ^
plugins/main/vlan/vlan_test.go:523:29: unused-parameter: parameter 'netNS' seems to be unused, consider removing or renaming it as _ (revive)
                                        _ = originalNS.Do(func(netNS ns.NetNS) error {
                                                               ^
plugins/meta/bandwidth/bandwidth_linux_test.go:205:27: unused-parameter: parameter 'n' seems to be unused, consider removing or renaming it as _ (revive)
                                Expect(hostNs.Do(func(n ns.NetNS) error {
                                                      ^
plugins/meta/bandwidth/bandwidth_linux_test.go:274:27: unused-parameter: parameter 'n' seems to be unused, consider removing or renaming it as _ (revive)
                                Expect(hostNs.Do(func(n ns.NetNS) error {
                                                      ^
plugins/meta/bandwidth/bandwidth_linux_test.go:341:27: unused-parameter: parameter 'n' seems to be unused, consider removing or renaming it as _ (revive)
                                Expect(hostNs.Do(func(n ns.NetNS) error {
                                                      ^
level=info msg="File cache stats: 144 entries of total size 998.0KiB"
level=info msg="Memory: 206 samples, avg is 311.5MB, max is 1826.8MB"
level=info msg="Execution took 20.434443709s"

[adrianchiris]

@squeed @dcbw can we get this one merged so it unblocks CI checks on other PRs ?