Modify pre-commit hook to check merge conflicts accidentally committed not at...

Modify pre-commit hook to check merge conflicts accidentally committed not at current merge commit (#1927)

.pre-commit-config.yaml

@@ -10,6 +10,7 @@ repos:
       - id: check-case-conflict
       - id: check-json
       - id: check-merge-conflict
+        args: [--assume-in-merge]
       - id: check-symlinks
       - id: check-yaml
         args: ["--unsafe"]