fix(mssql): attempt to support MERGE for backend

Author: deepyaman

ibis/backends/mssql/__init__.py

@@ -424,6 +424,8 @@ def _safe_raw_sql(self, query, *args, **kwargs):
         with contextlib.suppress(AttributeError):
             query = query.sql(self.dialect)
 
+        query = f"{query};"
+
         with self.begin() as cur:
             cur.execute(query, *args, **kwargs)
             yield cur