ci: restore checkout v1 for i386 job

Author: rwgk

.github/workflows/ci.yml

@@ -718,7 +718,7 @@ jobs:
 
     steps:
     # v1 required for i386/debian container; pinned to SHA to prevent dependabot updates
-    - uses: actions/checkout@4f1f4aec02e41874fa0262ea8ff5172d7978ad1e  # v1
+    - uses: actions/checkout@544eadc6bf3d226fd7a7a9f0dc5b5bf7ca0675b9  # v1
 
     - name: Install requirements
       run: |