Add sanity check to tell us if we're using log::warn! directly

.github/workflows/ci.yml

@@ -30,6 +30,10 @@ jobs:
         run: |
           ./scripts/check-parity-bw-extrinsics-benchmarks-weights.sh
 
+      - name: Check for direct usage of log::warn vs. warn_or_panic in migrations
+        run: |
+          ./scripts/check-usage-of-log-warn.sh
+
   fmt:
     name: Rustfmt
     runs-on: ubuntu-latest

scripts/check-usage-of-log-warn.sh

@@ -0,0 +1,13 @@
+#!/bin/bash
+
+set -xeuo pipefail
+
+OUTPUT=$(find . -wholename "*/migrations/*.rs"  | xargs grep "log::warn" || true)
+if [ -n "$OUTPUT" ]; then
+    echo "FAIL"
+    echo "$OUTPUT"
+    exit 1
+fi
+
+echo "PASS"
+exit 0