Adding upstream version 2.6.3.

Signed-off-by: Daniel Baumann <daniel@debian.org>

.github/workflows/golangci-lint.yml

@@ -0,0 +1,27 @@
+name: golangci-lint
+on:
+  push:
+    tags:
+      - v*
+    branches:
+      - master
+      - main
+  pull_request:
+jobs:
+  golangci:
+    name: lint
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+
+      - name: Set up Go
+        uses: actions/setup-go@v5
+        with:
+          go-version: 1.23.x
+
+      - name: golangci-lint
+        uses: golangci/golangci-lint-action@2226d7cb06a077cd73e56eedd38eecad18e5d837  #v6.5.0
+        env:
+          GOTOOLCHAIN: local
+        with:
+          version: v1.64