ci: bump golangci-lint to v2.5

This is a squashed backport of commits c1958d8, 1c2810b,
9e0f989, and 2aea861, bumping golangci-lint-action and
golangci-lint to latest versions (as of today).

Signed-off-by: Kir Kolyshkin <kolyshkin@gmail.com>

Author: kolyshkin

.github/workflows/validate.yml

@@ -39,9 +39,9 @@ jobs:
         run: |
           sudo apt -q update
           sudo apt -qy install libseccomp-dev
-      - uses: golangci/golangci-lint-action@v7
+      - uses: golangci/golangci-lint-action@v8
         with:
-          version: v2.1
+          version: v2.5
       # Extra linters, only checking new code from a pull request.
       - name: lint-extra
         if: github.event_name == 'pull_request'