Adding upstream version 2.52.6.

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

.github/workflows/vulncheck.yml

@@ -0,0 +1,37 @@
+name: Run govulncheck
+
+on:
+  push:
+    branches:
+      - v2
+    paths:
+      - "**"
+      - "!docs/**"
+      - "!**.md"
+  pull_request:
+    paths:
+      - "**"
+      - "!docs/**"
+      - "!**.md"
+
+jobs:
+  govulncheck-check:
+    runs-on: ubuntu-latest
+    env:
+      GO111MODULE: on
+    steps:
+      - name: Fetch Repository
+        uses: actions/checkout@v4
+
+      - name: Install Go
+        uses: actions/setup-go@v5
+        with:
+          go-version: "stable"
+          check-latest: true
+          cache: false
+
+      - name: Install Govulncheck
+        run: go install golang.org/x/vuln/cmd/govulncheck@latest
+
+      - name: Run Govulncheck
+        run: govulncheck ./...