Fix broken Kibana filters for Code Suggestions

The current list of Kibana links on Code Suggestions - Overview dashboard includes an incorrect Prometheus filter json.type that results in empty results. The mlops index does not include json.type attributes hence we should exclude this from the query.

https://dashboards.gitlab.net/dashboard/snapshot/Qk9HLvJHkrJDPE7cA4e0sukrQZy4Qi0o