[FIX] core: always close cursors at the exit of context managers

The call to `commit()` can fail during the flush of the environment
and raise an exception before the actual `COMMIT;`, leaving the
cursor unclosed.

This leaked cursor may hold locks that only be released when the GC
collects it. On low-traffic workers like the CronWorker, this can
lock usual database usages.

X-original-commit: 3cb3cec67c28ca147288103adb219e6da8694248
Part-of: odoo/odoo#93993

odoo/sql_db.py

@@ -198,9 +198,11 @@ class BaseCursor:
         return self
 
     def __exit__(self, exc_type, exc_value, traceback):
-        if exc_type is None:
-            self.commit()
-        self.close()
+        try:
+            if exc_type is None:
+                self.commit()
+        finally:
+            self.close()
 
 
 class Cursor(BaseCursor):