fix: update golangci-lint to v2 in CI and config

Upgrade from golangci-lint v1.53 to v2.1 in CI workflow and use v2
config format. Also update checkout and setup-go actions to latest.

Author: ravisuhag

.github/workflows/lint.yml

@@ -6,14 +6,14 @@ jobs:
   golangci:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
         with:
           fetch-depth: 0
-      - uses: actions/setup-go@v4
+      - uses: actions/setup-go@v5
         with:
           go-version: "1.20"
       - name: golangci-lint
-        uses: golangci/golangci-lint-action@v3
+        uses: golangci/golangci-lint-action@v6
         with:
-          version: v1.53
+          version: v2.1
           args: --timeout=5m

.golangci.yml

@@ -1,4 +1,5 @@
 version: "2"
+
 linters:
   enable:
     - errcheck