Narrow conflict-marker CI check to <<<<<<< and >>>>>>>

.github/workflows/ci.yml

@@ -13,8 +13,7 @@ jobs:
 
       - name: Reject merge conflict markers
         run: |
-          if git grep -nE '^(<<<<<<<|>>>>>>>|=======)' -- . \
+          if git grep -nE '^(<<<<<<<|>>>>>>>)' -- . \
-            ':(exclude)*.lock' \
             ':(exclude)package-lock.json'; then
             echo "::error::Merge conflict markers found in tracked files"
             exit 1