Add lock thred workflow

.github/workflows/ci.yml

@@ -1,4 +1,4 @@
-name: ci
+name: CI
 
 on:
   schedule:

.github/workflows/lock.yml

@@ -0,0 +1,32 @@
+name: Lock threads
+
+on:
+  schedule:
+    - cron: '0 0 * * *'
+
+jobs:
+  lock:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: dessant/lock-threads@v2
+        with:
+          github-token: ${{ github.token }}
+          issue-lock-inactive-days: '365'
+          issue-exclude-created-before: ''
+          issue-exclude-labels: ''
+          issue-lock-labels: 'Locked'
+          issue-lock-comment: >
+            This thread has been automatically locked since there has not been
+            any recent activity after it was closed. Please open a new issue for
+            related bugs.
+          issue-lock-reason: 'resolved'
+          pr-lock-inactive-days: '365'
+          pr-exclude-created-before: ''
+          pr-exclude-labels: 'Locked'
+          pr-lock-labels: ''
+          pr-lock-comment: >
+            This thread has been automatically locked since there has not been
+            any recent activity after it was closed. Please open a new issue for
+            related bugs.
+          pr-lock-reason: 'resolved'
+          process-only: ''